Money quantities are interpreted as decimals, typically dollars and cents to the hundredths place, and related through addition, subtraction, multiplication, or division in one- and multistep situations such as finding totals, change, costs for several items, or a unit price. Reasoning includes aligning place values, preserving the meaning of cents, estimating to check whether an answer is reasonable, and rounding monetary results when appropriate; advanced financial formulas, percentages beyond the decimal operations involved, and arbitrary-precision currency calculations are not included.
Money amounts use decimals: the digits to the left of the decimal are dollars, and the two digits to the right are cents. Always line up decimal points when adding or subtracting.
Example: A student buys 3 notebooks at 2.45$1.79$10.00$, how much change will they receive?
First, find the cost of the notebooks:
So, 3 notebooks cost 7.35$.
Now add the cost of the pen. Line up the decimal points:
The total cost is 9.14$.
Finally, subtract the total from the amount paid:
The student receives 0.86$ in change.
Check the answer by estimating: 2.50 \approx $7.50)$7.50+$1.80\approx $9.30$10.00-$9.30\approx $0.70$0.86$ is reasonable.
Click a topic below to practice the foundational skills you'll need, learn the steps, or master this skill
Earned ?