### All SAT Math Resources

## Example Questions

### Example Question #86 : Algebra

A theme park charges $10 for adults and $5 for kids. How many kids tickets were sold if a total of 548 tickets were sold for a total of $3750?

**Possible Answers:**

269

248

431

157

346

**Correct answer:**

346

Let *c* = number of kids tickets sold. Then (548 – *c*) adult tickets were sold. The revenue from kids tickets is $5*c*, and the total revenue from adult tickets is $10(548 – *c*). Then,

5*c* + 10(548 – *c*) = 3750

5*c* + 5480 – 10*c* = 3750

5*c* = 1730

*c* = 346.

We can check to make sure that this number is correct:

$5 * 346 tickets + $10 * (548 – 346) tickets = $3750 total revenue

### Example Question #87 : Algebra

Two palm trees grow next to each other in Luke's backyard. One of the trees gets sick, so Luke cuts off the top 3 feet. The other tree, however, is healthy and grows 2 feet. How tall are the two trees if the healthy tree is now 4 feet taller than the sick tree, and together they are 28 feet tall?

**Possible Answers:**

14 and 14 feet

11 and 17 feet

cannot be determined

8 and 20 feet

12 and 16 feet

**Correct answer:**

12 and 16 feet

Let *s* stand for the sick tree and *h* for the healthy tree. The beginning information about cutting the sick tree and the healthy tree growing is actually not needed to solve this problem! We know that the healthy tree is 4 feet taller than the sick tree, so *h* = *s* + 4.

We also know that the two trees are 28 feet tall together, so *s* + *h* = 28. Now we can solve for the two tree heights.

Plug *h* = *s* + 4 into the second equation: (*s* + 4) + *s* = 28. Simplify and solve for *h*: 2*s* = 24 so *s* = 12. Then solve for *h*: *h* = *s* + 4 = 12 + 4 = 16.

### Example Question #71 : Equations / Inequalities

Solve for *z*:

3(*z* + 4)^{3} – 7 = 17

**Possible Answers:**

2

8

–2

4

–8

**Correct answer:**

–2

1. Add 7 to both sides

3(*z* + 4)^{3} – 7 + 7= 17 + 7

3(*z* + 4)^{3} = 24

2. Divide both sides by 3

(*z* + 4)^{3} = 8

3. Take the cube root of both sides

*z* + 4 = 2

4. Subtract 4 from both sides

*z* = –2

### Example Question #72 : Equations / Inequalities

Jen and Karen are travelling for the weekend. They both leave from Jen's house and meet at their destination 250 miles away. Jen drives 45mph the whole way. Karen drives 60mph but leaves a half hour after Jen. How long does it take for Karen to catch up with Jen?

**Possible Answers:**

She can't catch up.

**Correct answer:**

For this type of problem, we use the formula:

When Karen catches up with Jen, their distances are equivalent. Thus,

We then make a variable for Jen's time, . Thus we know that Karen's time is (since we are working in hours).

Thus,

There's a logical shortcut you can use on "catching up" distance/rate problems. The difference between the faster (Karen at 60mph) and slower (Jen at 45mph) drivers is 15mph. Which means that every one hour, the faster driver, Karen, gains 15 miles on Jen. We know that Jen gets a 1/2 hour head start, which at 45mph means that she's 22.5 miles ahead when Karen gets started. So we can calculate the number of hours (H) of the 15mph of Karen's "catchup speed" (the difference between their speeds) it will take to make up the 22.5 mile gap:

15H = 22.5

So H = 1.5.

### Example Question #73 : Equations / Inequalities

Bill and Bob are working to build toys. Bill can build toys in 6 hours. Bob can build toys in 3 hours. How long would it take Bob and Bill to build toys working together?

**Possible Answers:**

**Correct answer:**

Bill builds toys an hour. Bob builds toys an hour. Together, their rate of building is . Together they can build toys in 2 hours. They would be able to build toys in 8 hours.

### Example Question #74 : Algebra

A hybrid car gets 40 miles per gallon. Gasoline costs $3.52 per gallon. What is the cost of the gasoline needed for the car to travel 120 miles?

**Possible Answers:**

**Correct answer:**

The car will be using of gas during this trip. Thus, the total cost would be .

### Example Question #91 : Gre Quantitative Reasoning

Jon invested part of $16,000 at 3% and the rest at 5% for a total return of $680.

Quantity A: The amount Jon invested at 5% interest

Quantity B: The amount Jon invested at 3% interest

**Possible Answers:**

Quantity A is greater

The two quantities are equal

The relationship cannot be determined from the information given

Quantity B is greater

**Correct answer:**

Quantity A is greater

First, let represent the invested amount at 3% and set up an equation like this:

Solve for , and you'll find that Jon invested $6,000 at 3% and $10,000 at 5%.

### Example Question #92 : Gre Quantitative Reasoning

Audrey, Penelope and Clementine are all sisters. Penelope is 8 years older than Clementine and 2 years younger than Audrey. If the sum of Penelope and Clementine's age is Audrey's age, how old is Clementine's age?

**Possible Answers:**

**Correct answer:**

Let = Audrey's age, = Penelope's age, and = Clementine's age.

Since , then .

Furthermore, , and .

Through substitution, .

### Example Question #93 : Gre Quantitative Reasoning

If and , what is the value of ?

**Possible Answers:**

**Correct answer:**

We could use the substitution or elimination method to solve the system of equations. Here we will use the elimination method.

To solve for , combine the equations in a way that makes the terms drop out. The first equation has and the second , so multiplying the first equation times 2 then adding the equations will eliminate the terms.

Multiplying the first equation times 2:

Adding this result to the second equation:

Isolate by dividing both sides by 7:

### Example Question #94 : Gre Quantitative Reasoning

If and , then what is the value of ?

**Possible Answers:**

**Correct answer:**

Since the expression we want just involves z and x, but not y, we start by solving for y .

Then we can plug that expression in for y in the first equation.

Multiply everything by 12 to get rid of fractions.

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