Whole-Number Addition/Subtraction
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ISEE Lower Level: Mathematics Achievement › Whole-Number Addition/Subtraction
At the beginning of the year, the town of Springfield had a population of 8,452. During the year, 112 babies were born, 78 people passed away, and 240 people moved into town. What was the population of Springfield at the end of the year?
8,278
8,486
8,726
8,882
Explanation
Start with the initial population and account for each change. Add the births: 8,452 + 112 = 8,564. Subtract the deaths: 8,564 - 78 = 8,486. Add the people who moved in: 8,486 + 240 = 8,726. The final population is 8,726.
A bicycle costs $215. Maria has saved $85 from her allowance and received $40 for her birthday. How much more money does she need to buy the bicycle?
$90
$125
$130
$175
Explanation
First, find the total amount of money Maria has by adding her savings and birthday money: $85 + $40 = $125. Next, subtract the amount she has from the cost of the bicycle to find out how much more she needs: $215 - $125 = $90.
A bakery started the day with a certain number of cupcakes. They first baked a new batch of 72 cupcakes. Then, they sold 150 cupcakes throughout the day. At closing time, 36 cupcakes were left. How many cupcakes did the bakery have at the very start of the day?
42
114
186
258
Explanation
This problem requires working backwards. Before the 150 cupcakes were sold, there were 36 + 150 = 186 cupcakes. This total of 186 was the amount after a new batch of 72 was baked. To find the starting amount, subtract the baked cupcakes: 186 - 72 = 114 cupcakes.
The fourth-grade classes set a goal to raise $1,200 for charity. Ms. Smith's class raised $345, and Mr. Jones's class raised $410. How much more money do they need to raise to meet their goal?
$445
$755
$790
$855
Explanation
First, find the total amount raised so far by the two classes: $345 + $410 = $755. Then, subtract the amount raised from the goal to find out how much more is needed: $1,200 - $755 = $445.
The town library has 5,480 books. The school library has 3,150 books. If the town library donates 600 books to the school library, what will be the new difference in the number of books between the two libraries?
2,930
1,130
1,730
2,330
Explanation
First, calculate the new number of books in each library. The town library will have 5,480 - 600 = 4,880 books. The school library will have 3,150 + 600 = 3,750 books. Then, find the new difference between the two amounts: 4,880 - 3,750 = 1,130 books.
Chloe has a collection of 152 stickers, and her brother Ben has 84 stickers. How many stickers does Chloe need to give to Ben so that they both have the same number of stickers?
34
68
118
236
Explanation
First, find the total number of stickers: 152 + 84 = 236. To have the same number, each would have half the total: 236 ÷ 2 = 118 stickers. The number of stickers Chloe needs to give away is the difference between her current amount and the equal share: 152 - 118 = 34 stickers. Alternatively, find the difference (152 - 84 = 68) and divide by 2 (68 ÷ 2 = 34).
David went to the store with $150. He bought a video game for $68 and a controller for $45. He also bought a snack for $4. How much money did he have left?
$33
$37
$82
$117
Explanation
First, find the total cost of all the items David bought: $68 + $45 + $4 = $113 + $4 = $117. Then, subtract the total cost from the money he started with to find the amount left: $150 - $117 = $33.
The drive from Boston to Denver is 1,972 miles. The Chen family drove 455 miles on the first day and 510 miles on the second day. How many miles do they still have to drive?
1,462
965
1,017
1,007
Explanation
First, calculate the total distance driven in the first two days: 455 + 510 = 965 miles. Then, subtract this distance from the total trip distance to find the remaining miles: 1,972 - 965 = 1,007 miles.
A bookstore started the week with 420 copies of a new novel. On Monday, they sold 65 copies. On Tuesday, they received a new shipment of 150 copies. On Wednesday, they sold 110 copies. How many copies did the bookstore have on hand at the end of Wednesday?
95
355
395
505
Explanation
Follow the inventory changes in order. Start: 420. After Monday's sales: 420 - 65 = 355. After Tuesday's shipment: 355 + 150 = 505. After Wednesday's sales: 505 - 110 = 395. The bookstore had 395 copies.
In a school competition, the Blue Team scored 245 points in the first round and 312 points in the second round. The Red Team scored 280 points in the first round and 295 points in the second round. After two rounds, how many more points did the Red Team have than the Blue Team?
18
35
52
557
Explanation
First, calculate the total score for each team. Blue Team's total: 245 + 312 = 557 points. Red Team's total: 280 + 295 = 575 points. Then, find the difference between their total scores: 575 - 557 = 18 points.