# Homework Help: What Is The Probability Of Picking A 3 Digit Number Divisible By 7

1. Oct 20, 2005

### mathelord

What Is The Probability Of Picking A 3 Digit Number Divisible By 7

2. Oct 20, 2005

### sanitykey

I'd start by thinking how many possibilities there are, so how many 3 digit integers (whole numbers) are there?

Then i'd consider how many numbers in this range are divisable by 7, a simpler example which may help you get started would be how many numbers from 1 to 70 are divisable by 7 the answer is just 70/7 = 10.

Once you've found out how many numbers between the range are divisable by 7, find out what percentage is this amount to the original range?

I hope this helps (and i hope it's right :tongue2: )

3. Oct 26, 2005

### tomcue

Mathelord,

I assume you are looking for whole number answers. Bear with my blue collar logic as I may have your answer. There are 900 possible 3 digit whole numbers. As they are consecutive, simply divide 900 by 7.

I believe your answer is 128/900 or 14.222%