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One Billion as Product of Two Numbers with No Zeros

Date: 12/12/2001 at 20:00:46
From: Danny Rubin
Subject: Math and multiples

The problem is: 

Write 1,000,000,000 as the product of two numbers, neither of which 
contains any zeros.

I cannot figure out the answer. I don't know where to start. This 
problem is totally confusing me. Help!

Thank you.

Date: 12/12/2001 at 22:43:59
From: Doctor Peterson
Subject: Re: Math and multiples

Hi, Danny.

Start by factoring the number as a product of primes. It will have 
only 5's and 2's. If you multiply 2 and 5, you get a number containing 
zero (a multiple of ten). So how can you split up the prime factors to 
express 1,000,000,000 as a product of two numbers that are not 
multiples of ten?

- Doctor Peterson, The Math Forum   
Associated Topics:
Elementary Multiplication
Elementary Puzzles
Middle School Factoring Numbers
Middle School Puzzles

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