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3.04 Unit costs

Worksheet
Cost rates
1

A 1.5 kg crab costs \$24. What is the cost per kilogram?

2

Calculate the price per unit if:

a

6 g costs \$0.84

b

43 mL costs \$3.44

c

13.2 m costs \$3.30

d

141 g costs \$15

e

274 mL costs \$7

f

26.2 m costs \$17

3

Calculate the amount per dollar to two decimal places, if you can buy:

a

349 g for \$9

b

709 mL for \$5

c

27 m for \$15

d

50 g for \$6.95

e

20 mL for \$5.25

f

140 m for \$2.18

Best buys
4

Consider the following sales:

  • 6 pencil cases for \$24 at Big Z.
  • 9 pencil cases for \$54 at X-mart.
a

What is the cost of a single pencil case at Big Z?

b

What is the cost of a single pencil case at X-mart?

c

Hence which is the best place to buy pencil cases, if you want the best price per item?

5

Consider the following prices of mangos:

  • 148 mangos for \$384.80 at shop A, or

  • 252 mangos for \$453.60 at shop B

a

What is the cost of a single mango at shop A?

b

What is the cost of a single mango at shop B?

c

Hence, which is the best place to buy mangos, if you want the best price per item?

6

There are three brands of bottled water in the market. Their prices are shown below:

  • Brand A: 2 L for \$3

  • Brand B: 7 L for \$11

  • Brand C: 15 L for \$9

Determine which brand is:

a

The best buy

b

The most expensive

7

Determine which shop has the cheaper price of the following:

a
  • Bill's Brilliant Bars: 152 grams for \$19, or

  • Charlie's Cheery Chocs: 90 grams for \$9

b
  • Frankie's Fabric: 16 metres for \$208, or

  • Chloe's Cloth: 18 metres for \$216, or

  • Marge's Material: 11 metres for \$121

c
  • Honest Anne's Soda: 600 mL for \$2.10, or

  • Fair Freddy's Pop: 2 L for \$9.00

8

A cafe sells coffees for \$4 each and offers one free coffee for every 6 coffees a customer buys.

a

Calculate the average price of one coffee for a customer who pays for 6 coffees.

b

How much more would a customer wanting to purchase 7 coffees have to pay if the special offer did not exist?

9

A direct factory outlet sells 40 L of detergent for \$694 to the public. Meanwhile, the local hardware store sells 8 L of the same detergent for \$92.

Calculate the discount in dollars per litre when buying from the hardware store, rather than the direct factory outlet.

10

Hairmart a wholesale hairdressing warehouse, sells 10 L bottles of shampoo for \$20. The same shampoo can be bought from retail stores at \$2 for 250 mL.

How much more expensive in dollars per litre is the shampoo when bought from the retail store?

11

James paid \$89 for 61 L of petrol in North Haverbrook. Valentina paid \$76 for 45 L of petrol in Dunkilderry.

a

How much does petrol cost per litre in North Haverbrook?

b

How much does petrol cost per litre in Dunkilderry?

c

In which suburb is petrol cheaper?

d

James buys 28 L of petrol in Oklachusetts. How much will this cost if the petrol price matches the best price between North Haverbrook and Dunkilderry?

12

At a grower’s market, durians are sold at Emporio for 56 cents per kilogram. At Greenery, each 4.5 kg durian is sold for \$3.50.

a

Calculate the price of 4.5 kg of durian from Emporio.

b

Which store is the best buy?

c

What is the most that the owner of FroteYote can charge for his 4.5 kg durians if he wants to beat the best buy by 5\%?

13

Consider the sale listings of two properties, the first property is a 350\text{ m}^{2} property priced at \$650\,000 and the second is a 459\text{ m}^{2} property listed for \$750\,000.

a

Calculate the price in dollars per square metre of the first property.

b

Calculate the price in dollars per square metre of the second property.

c

Based on the price per square metre, which listing appears to be a better buy?

14

The price of a 200 square metre apartment originally selling for \$662\,000 is reduced by 2\%. The price of an adjacent apartment 240 square metres in size is \$675\,000.

a

How much is the first apartment selling for per square metre after it has been discounted?

b

What is the second apartment selling for per square metre?

c

Which apartment is better value in terms of price per square metre?

d

What is the difference between the two apartments in terms of price per square metre?

15

A 500 g bag of almonds usually costs \$12.95 and a 200 g bag of almonds costs \$8.95. Today the 500 g bag is for sale at 10\% off.

a

Find the price per gram of the 500 g bag of almonds after the discount in cents. Round your answer to two decimal places.

b

Find the price per gram of the 200 g bag of almonds in cents. Round your answer to two decimal places.

c

Which bag of almonds is better value in terms of price per gram?

d

What is the difference between the two bags of almonds in terms of cents per gram?

16

2 L of milk, with an expiry date a week from today, costs \$3.00. A large 4 L bottle of the same brand, which expires in two days, is discounted to \$3.40.

a

What is the unit cost of the 2 L bottle?

b

What is the unit cost of the 4 L bottle?

c

Which is the better buy?

d

If a family usually take a week to get through 2 L of milk, is it worth spending more money to get the cheaper unit cost for the family? Explain your answer.

17

Carol needs 2 planks of wood to complete a cabinet she is going to sell. The planks of wood are sold in packs of 3 for \$40 per pack or in a pack of 10 for \$100 per pack.

a

What is the unit cost for the pack of 3?

b

What is the unit cost for the pack of 10?

c

Based on the unit costs, which is the better buy?

d

In Carol's circumstance, is it worth spending more money to get the cheaper unit cost? Explain your answer.

18

Explain when buying in bulk might not actually be worthwhile.

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1.1.4

compare prices and values using the unit cost method

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