Question

Find the missing terms.
3, _____, _____, 21 (arithmetic)

Answer 1

3, 9, 15, 21

Explanation:

3x1=3 v

3x2=6

3x3=9 v

3x4=12

3x5=15 v

3x6=18

3x7=21 v

Skip one each time, 3, 9, 15, 21