Answers

2016-07-14T12:27:34+08:00
Given:
a1 = 14, an = 196, d = 7, n = ?

Where...
a1 - first term that is divisible by 7
an - last term that is divisible by 7
d - common difference
n - number of terms

Solution:
an = a1 + (n - 1)d
196 = 14 + (n - 1) 7
196 = 14 + 7n - 7
196 = 7n + 7
7n = 196 - 7
7n = 189
n = 189 รท 7
n = 27

The ANSWER is 27.
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