Rosie has £15 to spend on pens and pencils. She has to buy the same number of pens as pencils.
What is the greatest number of pens she can buy?
Pens cost £0.32
Pencils cost £0.08

37

Step-by-step explanation:

Since you have to have the same amount of pens and pencils, they will have the same variable.  The variable, x, represents the amount.  Multiply x by the costs and add the two costs together.  Set it equal to 15 and solve.

0.32x + 0.08x = 15

0.40x = 15

(0.40x)/0.40 = 15/0.40

x = 37.5

Since she can't spend more than £15, round your answer down.  This gives you 37.  She can buy 37 pens.