I do not know how to solve these type of questions

   Find the number of zeros at the end of the product of5^6.6^7.7^8.8^9........50^51

... means multiplication

    i know that we have to count the no.of 5's and two's but i can't proceed can anyone do the needful

no of zero

will be gained just by seeing

the power of ten

and power of 2 and power of 5

in total product

let the power of 10=y

power of 2=x

power of 5=z

power of 5<power of 2

so obviosly

ans=y+z

check whether  x<z

otherwise

y+x