AMC8 2013 Problem 15

Past Contests AMC8 AMC 8 - 2013
1

If 3^{p}+3^{4}=90,2^{r}+44=76, and 5^{3}+6^{s}=1421, what is the product of p, r, and s ?

Answer Choices
A. 27
B. 40
C. 50
D. 70
E. 90