Best buy (unit price)
Name: _____________________ Date: __________
Show your thinking with numbers, words, or a drawing.
1. Oats: pack A is 400 g for $2.84, pack B is 300 g for $1.98. Which is better value? Give the cheaper unit price in cents per 100 g.
2. Coffee: pack A is 500 g for $3.25, pack B is 400 g for $4.00. Which is better value? Give the cheaper unit price in cents per 100 g.
3. Coffee: pack A is 500 g for $4.35, pack B is 300 g for $1.29. Which is better value? Give the cheaper unit price in cents per 100 g.
4. Flour: pack A is 300 g for $2.46, pack B is 500 g for $4.65. Which is better value? Give the cheaper unit price in cents per 100 g.
5. Oats: pack A is 200 g for $1.82, pack B is 300 g for $2.85. Which is better value? Give the cheaper unit price in cents per 100 g.
Answer key · Best buy (unit price)
1. 66
Pack A: 400 g is 4 lots of 100 g, so 284 ÷ 4 = 71 c per 100 g.
Pack B: 300 g is 3 lots of 100 g, so 198 ÷ 3 = 66 c per 100 g.
Pack B is better value at 66 c per 100 g.
2. 65
Pack A: 500 g is 5 lots of 100 g, so 325 ÷ 5 = 65 c per 100 g.
Pack B: 400 g is 4 lots of 100 g, so 400 ÷ 4 = 100 c per 100 g.
Pack A is better value at 65 c per 100 g.
3. 43
Pack A: 500 g is 5 lots of 100 g, so 435 ÷ 5 = 87 c per 100 g.
Pack B: 300 g is 3 lots of 100 g, so 129 ÷ 3 = 43 c per 100 g.
Pack B is better value at 43 c per 100 g.
4. 82
Pack A: 300 g is 3 lots of 100 g, so 246 ÷ 3 = 82 c per 100 g.
Pack B: 500 g is 5 lots of 100 g, so 465 ÷ 5 = 93 c per 100 g.
Pack A is better value at 82 c per 100 g.
5. 91
Pack A: 200 g is 2 lots of 100 g, so 182 ÷ 2 = 91 c per 100 g.
Pack B: 300 g is 3 lots of 100 g, so 285 ÷ 3 = 95 c per 100 g.
Pack A is better value at 91 c per 100 g.
Try it together
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