First, you do 65 ÷ 3 = 21.7 if rounding to the tenths, 21.67 if to the hundredths, and so on. Then you do 21.67 - 12 = 9.67. But since it is cards, I would say about 9 left.
First you add the £20 to the £70 to get £90. then you multiply 7×3 to get £21 spent on books. After that, multiply 12×4 to get £48 spent on games. then do 48 + 21 = 69. 90-69= 21.
