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प्रश्न
Find how many integers between 200 and 500 are divisible by 8.
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उत्तर
First term between 200 and 500 divisible by 8 is 208, and the last term is 496.
So, first term (a) = 208
Common difference (d) = 8
an = a + (n − 1)d = 496
⇒208 + (n − 1)8 = 496
⇒(n−1)8 = 288
⇒ n − 1 = 36
⇒n=37
Hence, there are 37 integers between 200 and 500 which are divisible by 8.
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