Question

Find the sum of all positive whole numbers x such that 2x-7 < 21.

Answer 1

x=14

Explanation:

2x-7<21

+7=0

2×<21+7=28

2×/2=0

2/28

=14

Answer 2

91

Explanation:

Trust me, it's an Aops question, and I got mastery on it, or blue if you want.