Fraction Classroom · 2.0.0 · Student pages

Add, Subtract & Check Fraction Amounts

Compose equal units, rename unlike fractions, regroup mixed numbers and check whether an answer makes sense.

Anonymous group code: __________ Date: __________

Pre-assessment

Use an anonymous code S01–S40, not a name. Suggested time: 15–20 minutes. Show your reasoning with a model, words or an equation. Use the same access supports on both occasions.

c203-pre-1. Find 1/3 + 1/4. Show how to make equal-sized units before adding.

c203-pre-2. A bottle holds 5/6 liter. After 1/3 liter is poured out, how much remains? Use equivalent fractions and include units.

c203-pre-3. Find 2 1/4 − 3/4. Show the exchange of one whole before subtracting.

c203-pre-4. A student rewrites 3 1/5 as 2 5/5 to prepare for subtraction. Correct the rewrite and explain the missing amount.

c203-pre-5. Someone claims 2/3 + 3/4 = 5/7. Reject or accept this using an estimate before finding the exact sum.

c203-pre-6. A trail is 1 1/2 km long. You walk 2/3 km. Is 1/6 km a reasonable remaining distance? Find the remainder and check by addition.

Post-assessment

Use an anonymous code S01–S40, not a name. Suggested time: 15–20 minutes. Show your reasoning with a model, words or an equation. Use the same access supports on both occasions.

Add, Subtract & Check Fraction Amounts

Pre-assessment

c203-pre-1. Find 1/3 + 1/4. Show how to make equal-sized units before adding.

c203-pre-2. A bottle holds 5/6 liter. After 1/3 liter is poured out, how much remains? Use equivalent fractions and include units.

c203-pre-3. Find 2 1/4 − 3/4. Show the exchange of one whole before subtracting.

c203-pre-4. A student rewrites 3 1/5 as 2 5/5 to prepare for subtraction. Correct the rewrite and explain the missing amount.

c203-pre-5. Someone claims 2/3 + 3/4 = 5/7. Reject or accept this using an estimate before finding the exact sum.

c203-pre-6. A trail is 1 1/2 km long. You walk 2/3 km. Is 1/6 km a reasonable remaining distance? Find the remainder and check by addition.

Post-assessment

c203-post-1. A jug receives 2/5 liter and then 1/2 liter. Find the combined amount and explain the equal-sized parts you used.

c203-post-2. A rope is 7/8 meter long. A 1/4-meter piece is cut off. Show the remaining length on a bar and as an equation.

c203-post-3. There are 4 1/3 cups of flour. A recipe uses 1 2/3 cups. Find the amount left and show a value-preserving exchange.

c203-post-4. Which is equal to 5 2/6: 4 6/6, 4 8/6, or 5 8/6? Explain by exchanging exactly one whole.

c203-post-5. Before solving 5/8 + 7/10, decide whether its sum is below or above 1. Then calculate and explain why 12/18 cannot be correct.

c203-post-6. A tank starts with 2 1/4 liters and ends with 5/6 liter. How much was used? Check that used plus remaining equals the starting amount.