Question

Find the number of terms in an AP 3,5,7,...21
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Answer 1

Answer:

10

Explanation:

Answer 2

Answer:

10

Explanation:

a=3

d=2

an=21

an = a+(n-1)d

21=3+(n-1)d

18 =(n-1 )2

9= n-1

n = 1o