Dudley has $20 he spends $15 of it on sweets. How much money does he have left?
$2 $8 $7 $5
the correct answer should be $5
The first thing you do to find the answer is identify the signs.
Next you do the subtraction.
The fourth Harry Potter book costs $29, and a Harry Potter book mark costs $2.50. How much money do I owe the book store?
Find the signs, and then do the math.