Q88 of 100 Page 312

The sum of the multiplication table of natural number ‘n’ is given by 55 × n. Find the sum of

(a) Table of 7


(b) Table of 10


(c) Table of 19

(a) Table of 7


put n = 7


55× 7 = 385


(b) Table of 10


put n = 10


55× 10 = 550


(c) Table of 19


put n = 19


55× 19 = 1045


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