Start here

You did these with your group. Now do them on your own — the model above is yours to copy.

1. 1

   Same stepsFinish what the group started. Use the model above, step for step.

   Try it together — then prove it: Arcade Depot sells 350 tokens for $38.50. What do we divide? We divide price by tokens: $38.50 ÷ 350 = ? What is the cost per token, and is it lower than $0.12? ($0.11 — yes, the better buy.) Now prove it: say why that move had to work at all — not just that it did.

   Show your work
2. 2

   Warm restartAbout how many pounds is 10 kilograms? (1 kg ≈ 2.2 lb)

   1. Aabout 22 pounds
   2. Babout 12.2 pounds
   3. Cabout 4.5 pounds
   4. Dabout 2.2 pounds

   How do you know?
3. 3

   Warm restartAbout how many centimetres are in 4 inches? (1 in ≈ 2.54 cm)

   1. Aabout 10.2 cm
   2. Babout 1.6 cm
   3. Cabout 6.5 cm
   4. Dabout 25.4 cm

   How do you know?
4. 4

   Warm restartA race is 5 kilometres long. About how many miles is that? (1 mi ≈ 1.6 km)

   1. Aabout 3.1 miles
   2. Babout 8 miles
   3. Cabout 5 miles
   4. Dabout 1.6 miles

   How do you know?

You answered these out loud. Now write them.

Answer, then say how you know — the reason is the part that counts.

1. 5

   Think it throughWhat is Printer A's unit rate?

   1. A30 tickets per minute
   2. B150 tickets per minute
   3. C5 tickets per minute
   4. D25 tickets per minute

   Why is that the answer?
2. 6

   Think it throughWhat is Printer B's unit rate?

   1. A25 tickets per minute
   2. B200 tickets per minute
   3. C8 tickets per minute
   4. D30 tickets per minute

   How do you know? Give a second reason as well.
3. 7

   Think it throughWhich printer is faster, and how long for 600 tickets?

   1. APrinter A, 20 minutes
   2. BPrinter B, 24 minutes
   3. CPrinter B, 20 minutes
   4. DPrinter A, 24 minutes

   Explain your thinking. What would have to change for a different choice to be right?
4. 8

   Back to the modelHow do you use unit rates to determine the better buy?

Use the words

Fill each blank with a word from the bank.

• Find the amount per ___ unit, then use it to compare the choices.
• A rate that gives the amount for exactly one unit is a ___.
• The option that costs less per item, found by comparing unit rates, is the ___.
• Showing how two amounts relate to each other is a ___.

Explain the thinking

1. 9

   Find the mistakeAnother student made this exact mistake in this lesson. Explain why it is wrong, then write what they should have done.

   The mistake: A common mistake in Solve Problems with Unit Rates is comparing the total prices instead of the cost per item — the deal with the smaller total can still cost more per unit.
2. 10

   Say moreHow did the unit rate help you decide the better buy between the two token suppliers in your table?
3. 11

   Write your ownWrite your own problem about this situation, then solve it and show the answer. The situation: A supermarket shelf tag shows two deals side by side for the same brand of juice boxes: a 6-pack for $3.00 and a 10-pack for $4.50.

   Show your work

Last check

These two come from Lesson 3.7. If they are shaky, that is the lesson to revisit — not this one.

1. 12

   Show what you knowExplain your thinking — A car travels 195 miles on 6 gallons of gas. What is the unit rate in miles per gallon?

   1. A32.5 miles per gallon
   2. B33 miles per gallon
   3. C30 miles per gallon
   4. D1,170 miles per gallon

   Explain your choice.
2. 13

   From Lesson 3.7Explain your thinking — A highway sign in Canada reads 100 km/h. Using 1 km ≈ 0.6 mi, is that faster or slower than 100 mi/h?

   1. ASlower — 100 km/h is about 60 mi/h
   2. BFaster — 100 km/h is about 160 mi/h
   3. CThe same, because both numbers are 100
   4. DYou cannot compare two different systems

   How do you know?
3. 14

   From Lesson 3.7Why do conversions between systems use ≈ rather than =?

   1. AThe conversion factors are rounded approximations
   2. BBecause metric units are always bigger
   3. CBecause the amounts are actually different
   4. DBecause ratios cannot be exact

   How do you know?

Be honest — this tells your teacher what to do next