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Question
If the common difference of an AP is 5, then what is a18 – a13?
Options
5
20
25
30
Solution
25
Explanation:
Given, the common difference of AP i.e., d = 5
Now,
As we know, nth term of an AP is
an = a + (n – 1)d
Where a = first term
an is nth term
d is the common difference
a18 – a13 = a + 17d – (a + 12d)
= 5d
= 5(5)
= 25
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