For a set of five positive integers, none greater than 100, the mean is 1.5 times the mode. If 31, 58, 98, x and x are the five integers, what is the value of x?
The numbers are 31, 58, 98, x, and x. The mode, M, is x since it's repeated twice. The mean, A, is
a= (31+58+98+2x)/5
(187+2x)/5=3/2x
(187+2x)=15/2x
2(187+2x)=15x
374+4x=15x
11x=374
x=34