Question

if the of first 6 multiple of 5 is equal to the sum of first n multiple of 7 then the value of n is
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Answer 1

Answer:

5

Step-by-step explanation:

he of first 6 multiple of 5 is equal to the sum of first n multiple of 7

5+10+15+20+25+30=7+14...an

105= n/2(2*7+(n-1) 7)

210= n(14+7n-7)

210 = n (7 +7n)

210/7= n (n+1)

30= n(n+1)

5 x 6 = n (n +1)

n = 5