If the first term is 1, and the ratio is 2
The first 4 terms are 1, 2, 4, 8
a. 7x + 52 (2x + 5x) (40 + 12)
b. 13x + 142 (2x+5x+6x) (40 + 12 - 10)
c. 246 (16 + 40 + 40 + 100 + 12 + 48 - 10)