maths D nov 07 question 18 (b) paper 1

[Sijan92]

b) A single carton of juice costs $4.20.
A special offer pack of 3 cartons costs $9.45.
Ali bought a special offer pack instead of 3 single cartons.
Calculate his percentage saving.

I have managed to do this question. i ended up in an answer like 3.15/12.6 X 100...but it is very hard to calculate this withount a calculator. can anyone please explain an easy way to solve this question???

 

[Zishi]

b) A single carton of juice costs $4.20.
A special offer pack of 3 cartons costs $9.45.
Ali bought a special offer pack instead of 3 single cartons.
Calculate his percentage saving.

I have managed to do this question. i ended up in an answer like 3.15/12.6 X 100...but it is very hard to calculate this withount a calculator. can anyone please explain an easy way to solve this question???

It is the only way. But you can do this by 3.15/12.60 and then removing the decimals, it would be 315/1260, and then simplify it.

 

[Sijan92]

thanks..