Prime numbers

The product of four prime numbers a,b,ca, b, c and dd is the sum of 55 consecutive numbers. Find the smallest possible value of a+b+c+da+b+c+d .

#NumberTheory

Note by Avanthi Vasudevan
4 years, 2 months ago

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Comments

Note that the sum of 55 consecutive numbers will always be divisible by 55; (sum equals 55*n ; where n is the middle term)
Hence; 2 of the primes must be 5 and 11; then to minimise the sum; take the other 2 primes as 2 and 2 or if you want different primes; 2 and 3.
So; the sum will be 20 or 21 according to whether duplication of primes is allowed or not.

Yatin Khanna - 4 years, 2 months ago

Pls help.. urgent...

Avanthi Vasudevan - 4 years, 2 months ago
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