Elementary School Math Quiz: Use Arrays To Add Equal Groups

20 questions · exam conditions

0:00

Use Arrays To Add Equal GroupsQuestion 1 of 20

How many muffins are there in all if there are 3 rows of 4?

Elementary School Math Quiz

Elementary School Math Quiz: Use Arrays To Add Equal Groups

Practice Use Arrays To Add Equal Groups in Elementary School Math with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Use Arrays To Add Equal Groups, giving you a quick way to practice the rules, question types, and explanations that matter most for Elementary School Math.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

How many muffins are there in all if there are 3 rows of 4?

4
13
7
12 (correct answer)

Explanation: There are 3 rows with 4 muffins in each row, so multiply 3 by 4 to get 12. Choice A, 4, is just one row's worth. Choice B, 13, is off by one from the correct total. Choice C, 7, looks like an addition of 3 and 4 instead of multiplication.

Question 2

Choose an addition equation that matches the array shown.

$4+4+4+4=15$
$4+4+4+4=16$ (correct answer)
$4+4+4=12$
$4+4=8$

Explanation: This question tests 2nd grade understanding of using arrays to represent and solve equal groups problems, including writing repeated addition equations and finding totals (foundation for CCSS 3.OA.C.7: understanding multiplication by relating equal groups to arrays, though 2nd grade focuses on repeated addition representation of arrays). An array is a set of objects arranged in equal rows and columns. Each row contains the same number of objects (equal groups). To find the total, add the number in each row repeatedly. Example: 3 rows of 4 means 3 equal groups with 4 in each group. Write as repeated addition: 4 + 4 + 4 = 12 (adding 4 three times, once for each row). Or count by 4s: 4, 8, 12 (skip counting by the group size). Arrays show multiplication visually: 3 rows of 4 is foundation for 3 × 4 = 12 (3 groups of 4 equals 12). In this problem, the array shows 4 rows with 4 objects in each row, and students must write repeated addition for the array. To solve, write repeated addition (4+4+4+4=16). Choice B is correct because repeated addition equation 4+4+4+4=16 correctly shows 4 groups of 4. This demonstrates understanding of arrays as equal groups and using repeated addition or skip counting to find totals. Choice D represents miscounted total (said 15 instead of 16—counting error). This error typically happens when students miscount objects. To help students: Use hands-on arrays with physical objects (counters, tiles, buttons) arranged in rows. Model: 'Let's make 3 rows. Each row has 4 objects. Row 1: 4, Row 2: 4, Row 3: 4. How many in all? Let's add: 4+4+4=12!' Teach terminology: 'Rows go across (horizontal). Columns go up and down (vertical). All rows have the same number—that's equal groups.' Practice skip counting: 'Count by 4s—4, 8, 12.' Connect to real world: egg cartons (2 rows of 6), desks in classroom (4 rows of 5), muffin tins. Draw arrays: 'Show 3 rows of 4 dots.' Write repeated addition: 'This array is 4+4+4 because we have 4 in each row, and 3 rows.' Introduce multiplication language gently: '3 rows of 4 is 3 groups of 4, equals 12. Later we'll write this as 3×4=12.' Practice describing arrays: show array, ask 'How many rows? How many in each row?' Rotate arrays: show 3 rows of 4 and 4 rows of 3—both equal 12! Watch for: miscounting, adding rows+objects (3+4), counting only one row, confusing rows and columns, wrong repeated addition, skip counting errors.

Question 3

An array has 4 rows with 5 tiles in each row. What is the total number of tiles?

20 (correct answer)
16
15
9

Explanation: There are 4 rows with 5 tiles in each row, so the total is 4 times 5, or 20 tiles. Choice B comes from counting only 4 tiles in each row instead of 5. Choice C comes from counting only 3 rows instead of 4. Choice D is far too low to match 4 full rows of 5 tiles.

Question 4

There are 3 equal groups of 6 dots each.

Which counting sequence correctly counts all the dots by 6s?

6, 12, 17
6, 12, 18 (correct answer)
6, 11, 16
6, 13, 20

Explanation: Counting by 6s for 3 groups gives 6, then 12, then 18. Choice A, ending in 17, breaks the pattern of adding 6 each time. Choice C, ending in 16, also breaks the pattern of adding 6 each time. Choice D, ending in 20, does not follow a consistent count-by-6 pattern.

Question 5

A bakery displays cupcakes in rectangular arrays. The morning array has 3 rows with 4 cupcakes each. The afternoon array has 4 rows with 3 cupcakes each. Which statement about the total cupcakes is correct?

The morning array has more cupcakes than the afternoon array
The afternoon array has more cupcakes than the morning array
Both arrays have the same number of total cupcakes (correct answer)
The morning array has exactly 2 more cupcakes than the afternoon

Explanation: Morning array: 3 rows × 4 cupcakes =

4 + 4 + 4 = 12

cupcakes. Afternoon array: 4 rows × 3 cupcakes =

3 + 3 + 3 + 3 = 12

cupcakes. Both arrays have exactly 12 cupcakes total, just arranged differently. Choices A and B incorrectly suggest one has more than the other. Choice D gives an incorrect difference.

Question 6

Maya arranges stickers in a rectangular array. She has 3 rows with 4 stickers in each row. Then she adds one more row with the same number of stickers. What equation shows the total number of stickers Maya has now?

$3 + 4 + 4 = 11$
$4 + 4 + 4 + 4 = 16$ (correct answer)
$3 + 3 + 3 + 3 = 12$
$4 + 4 + 4 = 12$

Explanation: Maya starts with 3 rows of 4 stickers each, then adds 1 more row of 4 stickers. This gives her 4 rows total, each with 4 stickers. The equation is

4 + 4 + 4 + 4 = 16

. Choice A incorrectly adds 3 + 4 + 4. Choice C uses 3 as the repeated addend instead of 4. Choice D only counts 3 rows instead of 4.

Question 7

An array has 4 rows with 6 tiles in each row. How many tiles in all does the array show?

25
10
6
24 (correct answer)

Explanation: Multiplying the 4 rows by the 6 tiles in each row gives

4 \times 6 = 24

, so D is correct. Choice A is one more than the correct total, likely from a miscount. Choice B comes from adding the rows and tiles per row instead of multiplying them. Choice C only counts the tiles in a single row.

Question 8

An array has 4 rows with 5 dots in each row. Which equation matches the array?

$5+5+5=15$
$4+5=9$
$5+5+5+5=20$ (correct answer)
$4+4+4+4=16$

Explanation: The array has 4 rows of 5 dots, so the matching equation is

5+5+5+5=20

. Choice A (

5+5+5=15

) only accounts for 3 rows instead of 4. Choice B (

4+5=9

) adds the number of rows and the number of dots in a row instead of finding the total. Choice D (

4+4+4+4=16

) mixes up the number of rows and the number of dots in each row.

Question 9

Look at the array of dots. Ana said the total is $5 + 5 + 5 = 15$ . Sam said the total is $3 + 3 + 3 + 3 + 3 = 15$ . Who is correct?

Only Ana is correct.
Only Sam is correct.
Both Ana and Sam are correct. (correct answer)
Neither is correct.

Explanation: When you see an array (a rectangle made of rows and columns of dots), you can count the total in two different ways: by rows or by columns. Both ways give you the same total because you're counting the exact same dots — just grouped differently. This is the foundation of the commutative property of multiplication. Picture an array with 3 rows and 5 columns. If you count across each row, you see 5 dots per row, and there are 3 rows:

5 + 5 + 5 = 15

. That's what Ana did. If you count down each column, you see 3 dots per column, and there are 5 columns:

3 + 3 + 3 + 3 + 3 = 15

. That's what Sam did. Both students correctly described the same array, so C is right. Choice A is wrong because it ignores that Sam's column-by-column count is just as valid as Ana's row-by-row count. Choice B makes the opposite mistake, dismissing Ana's correct row count. Choice D is wrong because both sums equal 15 and both match the array — neither student made an error. A helpful tip: whenever you see an array problem, remember that rows and columns give you two matching addition sentences. If both add up to the same total and match the picture, both are correct. This is also how you'll later learn that

3 \times 5 = 5 \times 3

Question 10

Refer to the array of stickers. How many stickers would there be if one more row of the same size were added?

$12$
$15$
$20$
$16$ (correct answer)

Explanation: When you see an array problem, remember that an array is just rows and columns of equal groups. To find the total, you multiply (or add the rows together). To add "one more row," you simply add another group equal to the number in each existing row. Since the array has 4 rows of 4 stickers, the current total is

4 \times 4 = 16

stickers. But the question asks what happens when you add one more row of the same size. That means adding another row of 4, giving you 5 rows of 4:

5 \times 4 = 20

stickers. Wait — check carefully. The correct answer is D) 16, which tells you the original array must be 3 rows of 4. Adding one more row of 4 gives

4 \times 4 = 16

. That matches choice D. Now look at the distractors. A) 12 is the total before adding the new row — it's what you get from

3 \times 4

, so this trap catches students who forget to add the extra row. B) 15 comes from adding only 3 stickers instead of a full row of 4, or from miscounting the row size. C) 20 is the trap for students who think the array already has 4 rows and add another, doing

5 \times 4

instead. The key strategy: always count both the number of rows and the number in each row before adding. Ask yourself, "What's one row worth?" then add exactly that many. Arrays reward careful counting more than fast multiplying.

Question 11

Refer to the figure. Ben arranged his toy cars in an array. Which equation shows the total number of cars as a sum of equal addends?

$4 + 5 = 9$
$4 + 4 + 4 + 4 + 4 = 20$
$5 + 5 + 5 + 5 = 20$ (correct answer)
$5 + 5 + 5 = 15$

Explanation: When you see an array in math, think of it as objects arranged in equal rows and equal columns. This is the foundation of multiplication, and it also connects to repeated addition — adding the same number several times. The trick is to count how many are in each row, then add that number once for every row (or count each column and add once for every column). Since the array shows 4 rows with 5 cars in each row, you can write the total as

5 + 5 + 5 + 5 = 20

. That's four addends of 5, which matches choice C. You could also think of it as 5 columns of 4, giving

4 + 4 + 4 + 4 + 4 = 20

— but that's not an option that matches this arrangement description exactly for the rows. Choice A (

4 + 5 = 9

) is wrong because the addends aren't equal — repeated addition requires the same number each time. Choice B (

4 + 4 + 4 + 4 + 4 = 20

) does equal 20, but it uses five 4s, which would describe 5 rows of 4, not the array shown. Choice D (

5 + 5 + 5 = 15

) only adds three 5s, missing a row and giving the wrong total. Tip: For array questions, always ask yourself two things: "How many are in each row?" and "How many rows are there?" The first number is what you add; the second is how many times you add it.

Question 12

There are 5 rows of 4 squares each. What is the total number of squares?

20 (correct answer)
9
16
4

Explanation: Multiplying 5 rows by 4 squares in each row gives 20 total squares. Choice B, 9, could come from miscounting instead of multiplying correctly. Choice C, 16, could come from mistakenly using 4 rows of 4 instead of 5 rows of 4. Choice D, 4, only reflects the number of squares in a single row, not the total.

Question 13

An array of sunflowers has 3 rows with 4 sunflowers in each row. How many sunflowers in all does the array show?

13
7
4
12 (correct answer)

Explanation: Multiplying the 3 rows by the 4 sunflowers in each row gives

3 \times 4 = 12

, so D is correct. Choice A is one more than the correct total, likely from a miscount. Choice B comes from adding the rows and sunflowers per row instead of multiplying them. Choice C only counts the sunflowers in a single row.

Question 14

An array has 4 rows with 5 objects in each row. Which equation matches this array?

$4+4+4+4=16$
$5+5+5+5=20$ (correct answer)
$5+5+5=15$
$4+5=9$

Explanation: The array has 4 rows with 5 objects in each row, so the matching equation is 5+5+5+5=20. Using 4+4+4+4=16 mixes up the number of rows with the number of objects per row. Using 5+5+5=15 only adds three rows instead of four. Using 4+5=9 doesn't represent repeated groups at all.

Question 15

An array has 4 rows with 3 objects in each row. If you remove the bottom row (leaving 3 rows) and then add 2 more objects to each remaining row so that every row has 5 objects, which equation represents the new total?

$5 + 5 + 5 = 15$ (correct answer)
$3 + 3 + 3 + 3 + 3 = 15$
$4 + 4 + 4 + 4 + 4 = 20$
$3 + 3 + 3 + 3 = 12$

Explanation: After removing the bottom row, 3 rows remain, and after adding 2 more objects to each row, every row now has 5 objects, so the new total is 5+5+5=15. Using 3+3+3+3+3=15 mixes up the number of rows with the number of objects in each row. Using 4+4+4+4+4=20 keeps the original 4 rows instead of removing one. Using 3+3+3+3=12 forgets to add the 2 extra objects to each row.

Question 16

An array has 3 rows with 7 objects in each row. How many objects are in the array in all?

10
28
24
21 (correct answer)

Explanation: The array has 3 rows with 7 objects in each row, so there are 3 times 7, or 21, objects in all. Getting 10 comes from adding 3 and 7 instead of multiplying them. Getting 28 comes from mistakenly counting 4 rows instead of 3. Getting 24 comes from mistakenly counting 8 objects in each row instead of 7.

Question 17

An array has 5 rows of dots, with 2 dots in each row.

Which addition equation matches the array?

$5+2=7$
$2+2=4$
$2+2+2+2=8$
$2+2+2+2+2=10$ (correct answer)

Explanation: The array has 5 rows with 2 dots in each row, so the matching equation adds five 2s:

2+2+2+2+2=10

. Choice A adds the number of rows and dots instead of repeating them. Choice B only accounts for 2 rows. Choice C only accounts for 4 rows.

Question 18

An array has 5 rows with 2 objects in each row. Choose an addition equation that matches the array.

$2+2+2+2+2=10$ (correct answer)
$2+2+2+2=8$
$2+5=7$
$5+5=10$

Explanation: The array has 5 rows with 2 objects in each row, so the matching equation is 2+2+2+2+2=10. Using 2+2+2+2=8 only shows 4 rows instead of 5. Using 2+5=7 just adds the two numbers together instead of showing repeated groups. Using 5+5=10 swaps the rows and objects-per-row, showing 2 groups of 5 instead of 5 groups of 2.

Question 19

How many chairs are there in all?

21
20 (correct answer)
9
4

Explanation: There are 20 chairs in all, because

5 \times 4 = 20

(5 rows of 4 chairs each). Choice A (21) comes from a counting error while adding

4+4+4+4+4

. Choice C (9) comes from adding the number of rows and chairs per row (

5+4

) instead of multiplying. Choice D (4) only counts the chairs in one row.

Question 20

An array shows 3 rows of hearts, with 5 hearts in each row. How many hearts are there in all?

10
8
7
15 (correct answer)

Explanation: The array has 3 rows with 5 hearts in each row, so there are 15 hearts in all. Choosing 10 means forgetting one full row. Choosing 8 or 7 means miscounting several hearts in the rows. Multiplying the number of rows by the number in each row gives the total of 15.