x Turn on thread page Beta
 You are Here: Home >< Maths

# Maths watch

1. "Simon can buy 3 pencils and have 49p change or he can buy five pencils and have 15p change.

Write this information as an equation for x, cost in pence for one pencil"

Okay so, 3x + 49 and 5x +15...... it's + of course cause you're getting money back. But to get the cost of one pencil you equate it......

3x + 49 = 5x + 15 and cost for one would be 17p wouldn't it?? Then it asks how much money does Simon have to start with. How would i figure that out????

edit - wouldn't you just add 17p to the change you are given, so wouldn't it be 98p?????
2. Correct.

He has (3x+49)p to start with, how much is that (given what x is...)

3x + 49 = 5x +15

So, 49 = 2x + 15, 2x = 34, x = 17

Sorry, and money to start with will just be the 3x + 49, so 3(17) + 49 which = 100
4. oh yesss, so just sub in x instead of adding it to the change given to get the money he started with which is £1..... thanks guys!!

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: February 14, 2010
Today on TSR

### Boyfriend slept with someone else

...we were on a break

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams