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1. Here is the link to a screenshot of the question. http://prntscr.com/bnu0g7

How would I answer this question???
2. (Original post by Jack_Tomlin)
Here is the link to a screenshot of the question. http://prntscr.com/bnu0g7

How would I answer this question???
I did this question in my gcse maths(9-1) mock!!

Its a fairly easy question, what you have to do is work out how many literes of water he uses in a year, find how much that is cubic meteres. Then times this by 0.9122 to find out how much it cost a year for using water. Add this to the amount of 28.20 and compare which one is cheaper
3. (Original post by Jack_Tomlin)
Here is the link to a screenshot of the question. http://prntscr.com/bnu0g7

How would I answer this question???
What have you tried?
4. Work out how many litres he uses per year.
5. (Original post by theBranicAc)
I did this question in my gcse maths(9-1) mock!!

Its a fairly easy question, what you have to do is work out how many literes of water he uses in a year, find how much that is cubic meteres. Then times this by 0.9122 to find out how much it cost a year for using water. Add this to the amount of 28.20 and compare which one is cheaper
Could you do a solution for it please? So what do i times 180 by? I don't know how I would convert litres to cubic litres
6. (Original post by Jack_Tomlin)
Could you do a solution for it please? So what do i times 180 by? I don't know how I would convert litres to cubic litres
It gives you the conversion factor.
7. (Original post by B_9710)
It gives you the conversion factor.
So how would i convert 180 litres to cubic metres?
8. (Original post by Jack_Tomlin)
Could you do a solution for it please? So what do i times 180 by? I don't know how I would convert litres to cubic litres
Times 180 by 365-> this gives the amount of literes in a year
Divide it by 1000, to find the out how much cubic meteres it is
9. (Original post by theBranicAc)
Times 180 by 365-> this gives the amount of literes in a year
Divide it by 1000, to find the out how much cubic meteres it is
Ok understand the first bit because he uses 180 litres a day and there is 365 days in a year (180 x 365 = 65700 litres)

I don't understand why you divide it by 1000?
Sorry
10. (Original post by Jack_Tomlin)
Ok understand the first bit because he uses 180 litres a day and there is 365 days in a year (180 x 365 = 65700 litres)

I don't understand why you divide it by 1000?
Sorry
Because 1 cubic metre= 1000 litres
11. (Original post by TheCe)
Because 1 cubic metre= 1000 litres
Still doesnt make sense dw
12. (Original post by Jack_Tomlin)
Still doesnt make sense dw
You know the unitary method?
13. (Original post by TheCe)
You know the unitary method?
nope
14. (Original post by Jack_Tomlin)
Still doesnt make sense dw
How are you doing the higher tier if you dont know basics like the unitairy method
15. (Original post by Jack_Tomlin)
nope
Well say:-
1000 litres = 1 cubic metre
then 180 litres = x cubic metres
now cross multiply
1000x = 180
x = 180/1000

Does it make sense now?
16. (Original post by theBranicAc)
How are you doing the higher tier if you dont know basics like the unitairy method
Im not doing the higher tier this was from the foundation specimen papers
17. (Original post by TheCe)
Well say:-
1000 litres = 1 cubic metre
then 180 litres = x cubic metres
now cross multiply
1000x = 180
x = 180/1000

Does it make sense now?
Is it because to get from 1000 to 1 cubic metre you divide by 1000 to cancel the 4 zeros?
18. If it helps, you can rewrite your equations with all the units in.

1000L = 1m3, so that's 1000L per m3.
To cancel the units, 180L per day/1000L per m3 gives you 9/50 m3 per day.
Now use these figures to work out cubic meters per year, hence find the cost per year.
19. (Original post by Jack_Tomlin)
Is it because to get from 1000 to 1 cubic metre you divide by 1000 to cancel the 4 zeros?
If it makes it easier for you to understand, then yeah take it that way.

But a better approach would be using the unitary method.
Or you can look at it this way. We know a cubic metre is a larger quantity than a litre, since only 1 cubic metre is equal to a 1000 litres.
In such a case, as in when converting from a larger quantity to a smaller quantity, you divide.
And when converting from a smaller quantity to a larger quantity, you multiply.

Does this help?
20. The hardest part is working out how many days in a year there is

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