The equation yˆ=-5.131x2+31.821x-3.333 approximates the number of people standing in line to catch a commuter train x hours after 5 a. m. What is the best estimate for the number of people in line at 8 a. m.?

a. 32

b. 40

c. 46

d. 77

Given that y is the number of people in the line after 5 am and there are already 3 hours that have passed for 8 am, we substitute 3 to the equation to find the answer.

y = (-5.131) (3²) + 31.821 (3) - 3.333

Simplifying,

y = 45.951

Thus, the answer is letter C. 46.