3 notebooks at $2.45 each, paid with $10 — how much change?
Maya buys three notebooks. Each notebook costs two dollars and forty-five cents. She pays with a ten-dollar bill. How much change does she get back?
This problem has two steps. First we'll find the total cost. Then we'll subtract from ten dollars to find the change.
Step one: multiply two-point-four-five by three to get the total cost.
Three times two-point-four-five equals seven dollars and thirty-five cents. Keep the decimal point lined up.
Let's check. Two-point-four-five rounds to two-point-five, and three times two-point-five is seven-point-five. Our answer of seven-point-three-five is very close, so it makes sense.
Step two: subtract the cost from ten dollars. Line up the decimal points carefully.
Ten minus seven-point-three-five equals two dollars and sixty-five cents.
Quick check: ten minus seven is three, and our answer is just under three. That fits!
Maya gets two dollars and sixty-five cents in change. When problems have many steps, plan first, compute carefully, and check that your answer is reasonable.