Answer: 13%
Step-by-step explanation:
The formula to find the simple interest is given by :-
, where P is the principal amount, r is rate of interest () in decimal and t is the time ( in years).
Given : P = $19,100 , I=$9932.00 and t= 4 years
Substitute all the above values in the formula , we get

In percent , 
Hence, the rate of interest = 13%
Sorry what grade are you in
Area = 1/2 * base * height
= 1/2 * 20 * 6
= 1/2 * 120
= 60 ft^2
The student had a 40% error estimate