Thread: Not sure I understand...

Hi,

Could someone please explain this to me....

"Write a formula to calculate the total cost, £T, of B Maths books each costing £P and B Physics books each costing twice as much as each Maths book."

The answer is T = 3BP

What i'm not sure about is where the 3 comes into play?

Is it

B Maths books EACH costing... = 1

B Physics books costing TWICE as much as EACH maths book = 2

so thats where the 3 comes from or am I completely on the wrong lines!!!!

My initial thought would have been T = 2BP but thats wrong...

Thanks in advance, I'm struggling with maths at the moment!

Originally Posted by c19h28o2

Hi,

Could someone please explain this to me....

"Write a formula to calculate the total cost, £T, of B Maths books each costing £P and B Physics books each costing twice as much as each Maths book."

The answer is T = 3BP

What i'm not sure about is where the 3 comes into play?

Is it

B Maths books EACH costing... = 1

B Physics books costing TWICE as much as EACH maths book = 2

so thats where the 3 comes from or am I completely on the wrong lines!!!!

My initial thought would have been T = 2BP but thats wrong...

Thanks in advance, I'm struggling with maths at the moment!

As you say. The Math book costs x and the Physics book costs 2x. So if you buy B Math books and B Physics books you are going to pay
Bx + B(2x) = 3Bx

-Dan

Thanks Dan,

Suppose its just a way of thinking!