6.AT.3 Group 1 · Extra Support

Practice Set · Part 1

Ratio Reasoning: Convert Measurements within the Same System

Pick up where we left off

Name: Date: Group:

Where we left off

Our goal: With my small group, I can use ratio reasoning to convert between units within the same measurement system — one step at a time, with support.

The big idea: A conversion factor is a ratio between two units. To change to a smaller unit, multiply, because you need more of the smaller unit.

Model to copy — Example · Feet to inches

  1. Riders on a ride must be at least 44 inches tall. A child is 4 feet tall. Can the child go on the ride?
  2. Notice that the units are different: 44 inches and 4 feet
  3. Write 1 foot and 12 inches in the table.
  4. Find the scale factor for the feet: 4 ÷ 1 = 4
  5. Multiply the inches by the same factor: 12 × 4 = 48
  6. Compare the two heights: 48 > 44
  7. The child is 48 inches tall. 48 > 44, so the child can go on the ride.

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.

    Let's do one together: Diamond wants to drink 4 liters of water. Her bottle holds 500 milliliters. How many times does she fill the bottle? How many milliliters are in 1 liter? (1,000) What scale factor takes 1 liter to 4 liters? (4) Multiply 1,000 by 4. How many milliliters are in 4 liters? (4,000 mL) How many 500 mL bottles make 4,000 mL? (8, because 4,000 ÷ 500 = 8.)

    My first step is ___ , because the problem asks for ___ .

    Show your work
  2. 2

    Warm restartRecipe A uses 2 lemons for 4 cups of water. Recipe B uses 3 lemons for 4 cups of water. Which recipe is more lemony?

    1. ARecipe A
    2. BThey are the same
    3. CRecipe B
    4. DYou cannot tell
  3. 3

    Warm restartWhich ratio is greater: 3:4 or 5:8?

    1. A5:8
    2. B3:4
    3. CThey are equal
    4. DCannot determine
  4. 4

    Warm restartChef A uses 2 cups of cheese for every 8 crackers. Chef B uses 3 cups of cheese for every 9 crackers. Who uses more cheese per cracker?

    1. AChef A
    2. BChef B
    3. CThey use the same amount
    4. DCannot determine
3.6 Small Group · Group 1 · Practice SetPart 1 of 4
6.AT.3 Group 1 · Extra Support

Practice Set · Part 2

Ratio Reasoning: Convert Measurements within the Same System

Keep going

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 throughHow many inches are in 4 feet?

    1. A3 inches
    2. B16 inches
    3. C44 inches
    4. D48 inches

    Why is that the answer?

    I chose ___ because ___ .

  2. 6

    Think it throughA bottle holds 500 milliliters. How many bottles make 4 liters?

    1. A4
    2. B8
    3. C500
    4. D2,000

    How do you know?

    I chose ___ because ___ .

  3. 7

    Think it throughYou convert 96 ounces to pounds (16 ounces = 1 pound). Should the number get bigger or smaller?

    1. ABigger, because 96 is already large
    2. BSmaller, because pounds are the larger unit
    3. CIt stays the same
    4. DYou cannot tell without the ratio table

    Explain your thinking.

    I chose ___ because ___ .

  4. 8

    Back to the modelWhy does converting to a smaller unit always make the NUMBER bigger, even though the amount stays exactly the same?

    When the unit gets ___, it takes ___ of them to make the same amount, so I ___.

Sort it again — on paper this time

Write the letter of the group each one belongs in.

A — Multiply (to a smaller unit)B — Divide (to a larger unit)
3.6 Small Group · Group 1 · Practice SetPart 2 of 4
6.AT.3 Group 1 · Extra Support

Practice Set · Part 3

Ratio Reasoning: Convert Measurements within the Same System

Words and reasoning

Word bank · Banco de palabras

Conversion factor (Factor de conversión)Unit ratio (Razón unitaria)Convert (Convertir)Measurement system (Sistema de medidas)Double number line (Recta numérica doble)Ratio table (Tabla de razones)Ratio Reasoning (Razonamiento con razones)Proportion (Proporción)

Use the words

Fill each blank with a word from the bank.

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 when converting within a measurement system is choosing the operation by habit instead of by unit size — multiplying every time.
  2. 10

    Say moreYou sorted ratio pairs into equivalent and not equivalent. How does ratio reasoning, like cross-multiplying, prove that 4:7 and 12:21 are equivalent?

    I reasoned that 4:7 and 12:21 are ___ because ___.

  3. 11

    Change one numberGo back to Part 1 and pick one problem you already solved. Change one number in it, then solve your new version. Show every step.

    If ___ changed to ___ , then ___ .

    Show your work
3.6 Small Group · Group 1 · Practice SetPart 3 of 4
6.AT.3 Group 1 · Extra Support

Practice Set · Part 4

Ratio Reasoning: Convert Measurements within the Same System

Show what you know

Last check

These two come from Lesson 3.5. If they are shaky, that is the lesson to revisit — not this one.

  1. 12

    Show what you knowQuick check — you've got this: There are 4 cups in 1 quart. A soup recipe calls for 5 quarts of broth. How many cups is that, and why?

    1. A1.25 cups, because I divide 5 by 4
    2. B5 cups, because the amount does not change
    3. C9 cups, because I add 5 + 4
    4. D20 cups, because cups are smaller so I multiply: 5 × 4

    Explain your choice.

    I know it is ___ because ___ .

  2. 13

    From Lesson 3.5Quick check — you've got this: A bakery sells 4 muffins for $10 and another bakery sells 6 muffins for $14. Which bakery has the lower price per muffin?

    1. AThe first bakery
    2. BSame price
    3. CCannot determine
    4. DThe second bakery
  3. 14

    From Lesson 3.5Which shop is the better deal?

    1. AMario's, because $18 is less than $25
    2. BMario's, because 2 is less than 3
    3. CSal's, because $8.33 per pizza is less than $9.00
    4. DThey cost the same

Be honest — this tells your teacher what to do next

I can…Not yetGetting thereGot it
I can use ratio reasoning to convert between units within the same measurement system — one step at a time, with support.
I can explain why it works: A conversion factor is a ratio between two units. To change to a smaller unit, multiply…
I can talk through each step out loud using a sentence frame and the lesson's key words.

One question I want to ask my group next time