Need help explaining this answer! asap please

Me and my boyfriend are currently doing foundation maths, and after asking help for a question and me explaining it, he still doesn't understand it. I'm not the best at explaining things so could anybody put this better?

Pat and Juile share some money in the ratio 2:5
Juile gets £45 more than pat.
How much did Pat get?

I said:

If she gets £45 more, then 2-5 must be the rest of her money. So 2-5=3. So if someone had the ratio 3, they will have £45. 45/3= 15, so 15 is one ratio. 2*15 is 30, so pat got £30

He didn't get why we need to take away the ratios (Probably his teacher's fault telling him to always plus the ratios when working out money to give out questions) so I said:

2-5 is 3, so julie has 3 ratios more than pat, and these 3 ratios are £45. when we divide £45 by 3 it makes 1 ratio.
Pat has 2. Julie has 5. We are told Julie has £45 more. If we minus 2 and 5, we get three. Since Julie has 5 ratios more, minusing what Pat has to what Julie has will make Pat end up with 0, and Julie end up with 3 ratios.
These 3 ratios must be £45 as 3 is more than 2, 3+5 is 5 and this is how many ratios Julie has.
If you minus 2 from 5 you get 3 ratios, this is £45 as Julie gets £45 more than Pat

Can anybody explain why we minus them better?

Reply 1

davros

16

Original post by idontevenbeth

Me and my boyfriend are currently doing foundation maths, and after asking help for a question and me explaining it, he still doesn't understand it. I'm not the best at explaining things so could anybody put this better?

Pat and Juile share some money in the ratio 2:5
Juile gets £45 more than pat.
How much did Pat get?

I said:

If she gets £45 more, then 2-5 must be the rest of her money. So 2-5=3. So if someone had the ratio 3, they will have £45. 45/3= 15, so 15 is one ratio. 2*15 is 30, so pat got £30

He didn't get why we need to take away the ratios (Probably his teacher's fault telling him to always plus the ratios when working out money to give out questions) so I said:

2-5 is 3, so julie has 3 ratios more than pat, and these 3 ratios are £45. when we divide £45 by 3 it makes 1 ratio.
Pat has 2. Julie has 5. We are told Julie has £45 more. If we minus 2 and 5, we get three. Since Julie has 5 ratios more, minusing what Pat has to what Julie has will make Pat end up with 0, and Julie end up with 3 ratios.
These 3 ratios must be £45 as 3 is more than 2, 3+5 is 5 and this is how many ratios Julie has.
If you minus 2 from 5 you get 3 ratios, this is £45 as Julie gets £45 more than Pat

Can anybody explain why we minus them better?

It's easier to explain in terms of algebra - but would that confuse you as you' re doing Foundation?

Basically, if Pat and Julie divide something in the ratio 2:5 that means that for every 2 portions Pat gets, Julie gets 5. So, if there were exactly 7 pounds to share, Pat would get 2 and Julie would get 5.

If you add the 2 and the 5 together, you can think of the whole amount as divided into 7 portions - Pat gets 2 of these and Juliie gets 5 of them.

Julie gets £45 more than Pat means that Julie's "additional 3 portions" are worth £45, so 1 portion is worth £15 and Pat gets 2 portions = 2 x £15 = £30. You can check that Julie gets £75 and the total amount is £105.

Does this help?

Reply 2

TenOfThem

18

You can use this

Julie = 5
Pat = 2
Difference = 3

You can times by anything you want

For example (x3)

Julie = 15 (5x3)
Pat = 6 (2x3)
Difference = 9 (3x3)

But you are given the difference

Julie = (5x?)
Pat = (2x?)
Difference = 45 = (3x?)

The last bit tells you that ?=15

So julie = 75 and Pat = 30

Reply 3

Matt San

Original post by davros

It's easier to explain in terms of algebra - but would that confuse you as you' re doing Foundation?

Basically, if Pat and Julie divide something in the ratio 2:5 that means that for every 2 portions Pat gets, Julie gets 5. So, if there were exactly 7 pounds to share, Pat would get 2 and Julie would get 5.

If you add the 2 and the 5 together, you can think of the whole amount as divided into 7 portions - Pat gets 2 of these and Juliie gets 5 of them.

Julie gets £45 more than Pat means that Julie's "additional 3 portions" are worth £45, so 1 portion is worth £15 and Pat gets 2 portions = 2 x £15 = £30. You can check that Julie gets £75 and the total amount is £105.

Does this help?

Or, another way of putting it is:
There are 7 portions; Pat gets 2 portions and Julie gets 5 portions which is the same as (2 + 3) portions. We are told that 3 portions is £45 so one portions must be £45/3 =£15.
Therefore 2 portions = £30 and 5 portions = £75

Edit: Oh, and to answer your query on why minus the 2 from 5 is you are effectively getting rid of the initial bits in order to find out the what the extra bit i.e.£45 is in terms of the portions.

(edited 11 years ago)

Reply 4

idontevenbeth

OP

5

Original post by davros

It's easier to explain in terms of algebra - but would that confuse you as you' re doing Foundation?

Basically, if Pat and Julie divide something in the ratio 2:5 that means that for every 2 portions Pat gets, Julie gets 5. So, if there were exactly 7 pounds to share, Pat would get 2 and Julie would get 5.

If you add the 2 and the 5 together, you can think of the whole amount as divided into 7 portions - Pat gets 2 of these and Juliie gets 5 of them.

Julie gets £45 more than Pat means that Julie's "additional 3 portions" are worth £45, so 1 portion is worth £15 and Pat gets 2 portions = 2 x £15 = £30. You can check that Julie gets £75 and the total amount is £105.

Does this help?

I'm actually in set 2 maths so I'm doing higher, but everyone has to do the foundation exam, that helped a bit he said he kind of understood it :smile:

Reply 5

SPQR

Original post by idontevenbeth

I'm actually in set 2 maths so I'm doing higher, but everyone has to do the foundation exam, that helped a bit he said he kind of understood it :smile:

Find a better boyfriend. One who can actually do maths...

Reply 6

davros

16

Original post by idontevenbeth

I'm actually in set 2 maths so I'm doing higher, but everyone has to do the foundation exam, that helped a bit he said he kind of understood it :smile:

Glad I could help a bit :smile:

Reply 7

idontevenbeth

OP

5

Original post by SPQR

Find a better boyfriend. One who can actually do maths...