**< Go back to IVY GLOBAL SAT GUIDE 3RD EDITION or Study Home**

## Question Explanations For

##
*Problem Solving and Data Analysis (Modeling Data)*

1 2 3 4 5 6 7 8 910

## 1.

The Correct Answer is (B) —
Notice that as the temperature increases, the reaction time decreases. This means that the slope will be negative. The correct answer choice is B.

## 2.

The Correct Answer is (B) —
Based on the graph, we can see that when tickets are priced at $3.00, the number of tickets purchased is slightly less than 300. The correct answer choice is B.

## 3.

The Correct Answer is (D) —
If tickets are sold at $4 each, then the number of tickets purchased is 200. Therefore, the total revenue is $4 x 200 = $800. The correct answer choice is D.

## 4.

The Correct Answer is (C) —
Based on the graph, we can tell that the maximum fuel economy of this car is approximately halfway between 30 and 40 mpg. It looks less than 50 and greater than 25, but closer to 50 than to 25, which makes C the best answer.

## 5.

The Correct Answer is (C) —
The only other point on the graph where the car has a fuel economy of 18 mpg is when it is at a little over 75 mph. The correct answer choice is C.

## 6.

The Correct Answer is (A) —
Based on the line of best fit, the annual salary of an employee with 4 years of experience is slightly less than $60,000. The correct answer choice is A.

## 7.

The Correct Answer is (A) —
Because all the y-intercepts in the answer choices are 38, we must look at the slope to distinguish between different lines. We know that the slope must be positive and that it must be greater than 1 because for every increase in x, there is a much greater increase in the y-value. Therefore, the correct answer choice is A.

## 9.

The Correct Answer is (4) —
At the 0th hour, the number of bacteria is 20. After three hours, the population is 100. After four hours, it’ s 144. That means the population reached 140 sometime during the fourth hour. Based on the table, in order for the population to grow to 20 x 7 =140, it must have grown for four hours.

## 10.

The Correct Answer is (6) —
After 11 hours, there are 46(11) - 8 = 498 bacteria, whereas after 2 hours, there are 46(2) - 8 = 84. Therefore, there are approximately 498/ 84 = 6 times more.