Digital PSAT Math Practice Question 187: Answer and Explanation

Question: 187

A new business uses a crowdfunding website to raise money for its expansion. The graph below plots the number of new investment pledges per week, collecting the data once at the end of each week after the crowdfunding has begun (For example, Week 1 gives the total number of pledges at the very end of week 1).

A marketing professional defines the point at which something goes viral as the point at which the item shifts from linear to exponential growth. During what week does the value of the new investment pledges become viral?

• A. 2
• B. 3
• C. 6
• D. 10

Correct Answer: C

Explanation:

(C) The slope of the function is steady and linear until around week 6, at which point it starts curving upwards exponentially. An exponential function is one that goes up at a rapidly increasing rate or goes down at a rapidly decreasing rate, as opposed to a steady, linear rate.