MCQ
The common difference of an $AP,$ whose $n^{th}$ term is $an = (3n + 7),$ is :
- ✓$3$
- B$7$
- C$10$
- D$6$
✓
Answer
Correct option: A.
$3$
$ a_n=3 n+7 $
$ a_1=3 \times 1+7=10 $
$ a_2=3 \times 2+7=13 $
$ d=a_2-a_1 $
$d = 13 - 10$
$d = 3$
common difference $= 3$
$ a_1=3 \times 1+7=10 $
$ a_2=3 \times 2+7=13 $
$ d=a_2-a_1 $
$d = 13 - 10$
$d = 3$
common difference $= 3$
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