Answer:
Step-by-step explanation:
The easiest way to do this is either to find a pattern or list them. We'll list them first.
3 9 15 21 27 33 39 45 51 57 63 69 75 81 87 93 99
17 but there is a pattern
Starting with 3, add 6 to every number you find in the series. There is a formula that covers this
l = a + (n- 1)*d
a = 3
l = 99
d = 6
99 = 3 + (n - 1)*6 Subtract 3
99 - 3 = (n - 1)*6
96 = (n - 1)*6 Divide by 6
96/6 = (n -1)*6/6
16 = n - 1 Add 1 to both sides.
16+1 = n - 1 + 1 Combine
17 = n
