multiplication problem

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BabaPabz
Posts: 50
Joined: Wed Sep 18, 2019 2:57 pm

multiplication problem

Post by BabaPabz »

If x=1 × 2× 4× 7× 9× 11× 5× 11× 29× 5× 10, How many zeros are there in the value of x?

Anyone know how to approach this one?
solimum
Posts: 1420
Joined: Wed May 09, 2007 3:09 pm
Location: Solihull, West Midlands

Re: multiplication problem

Post by solimum »

Do they mean "zeroes at the end"? in which case you look for whether the result is divisible by 10, 100, 1000 or higher multiples of 10 (look for ways of making 10 as a factor, either as 10 on its own or as 5 x 2)

If they mean "zeroes somewhere in the final number" I can't immediately think of a clever trick to answer that....
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