Q10 of 110 Page 53

Find the sum of all natural numbers between 300 and 500 which are divisible by 11.


Series of all natural numbers divisible by 11 between 300and 500 is:

308, 319,………………………………495


In the A.P.


First term = 308


Last term = 495


Common difference = 11


Nth term = a + (n–1) d


⇒ 495 = 308 + (n–1)11


⇒ 187 = (n–1)11


⇒ 17 = (n–1)


⇒ n = 18


Sum of terms =


⇒ Sum of terms =


⇒ Sum of terms =


⇒ Sum of terms = 7227


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