can you tell me the digit sum(digit sum of
1789=1+7+8+9=25=2+5=7) of p=13258*15784*32547*36587*4304
you have 3mintz to do it.



can you tell me the digit sum(digit sum of 1789=1+7+8+9=25=2+5=7) of p=13258*15784*32547*36587*4304..

Answer / anonymus

digit sum(a*b)= digit sum(digit sum(a)*digit sun(b))
(since digit sum(a * AB...Z)= digit sum(digit sum(a*A)+digit sum(a*B)+...digit sum(a*Z))
=It is easy to verify that digit sum(a*b)=digit sum(digit sum(a)+digit sum(b))(Assume a,b here as single digit number.)
=so applying this result recoursively we get, digit sum(a*b*c)=digit sum(digit sum(a)+digit sum(b)+digit sum(c)).
There fore, digit sum(p)=digit sum(digit sum(13258)+digit sum(15784)+digit sum(32547)+digit sum(36587)+digit sum(4304)))
=digit sum(digit sum(19)+digit sum(25)+digit sum(21)+digit sum(30)+digit sum(12))
=digit sum(2+7+3+3+3)
=digit sum(18)
=9
So,digit sum(p)=9.
Hence Result...

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