Need a Mathmatician..

Customers at a shop who spend £100 or more can pay by these methods.
A 12 payments Each payment is 10% of the cost price
B 24 payments Each payment is 6% of the cost price
C 36 payments Each payment is 4% of the cost price
Which method is the cheapest?
You must show your working.

Depends how much they actually spend

Posted from TSR Mobile

Customers at a shop who spend £100 or more can pay by these methods.
A 12 payments Each payment is 10% of the cost price
B 24 payments Each payment is 6% of the cost price
C 36 payments Each payment is 4% of the cost price
Which method is the cheapest?
You must show your working.

For method A, you end up spending 12x10=120% of the cost price.
For method B, you end up spending 24x6=144% of the cost price.
For method C, you end up spending 36x4=144% of the cost price.

Hence, method A is the cheapest.

Yeh this is the answer in the aqa mark scheme but i dont know how you went about to find that answer... can you please give an explanation on the method...the question really had me baffled. Much appreciated

I'll give you an example:
Let us stipulate you had an amount of £100.00, ok?

A) In the first scenario, paying in increments of 12 with 10% of the cost price (£10.00) you will be paying £120.00.

B) In the second scenario, using the same amount, you will pay 6% (£6.00) 24 times so you will end up paying a total of £144.00.

C) In the final scenario, you will also be paying £144.00 following the same process.

From the example alone we are able to see that A is the most reasonable options and as we used a stipulated amount of £100.00 we can easily express it in percentages as the user before has shown.

Yeh this is the answer in the aqa mark scheme but i dont know how you went about to find that answer... can you please give an explanation on the method...the question really had me baffled. Much appreciated