Lesson 3.93.9 Small Group · Group 1
Group 1 · Set BSecond form · new problems, same idea
Learning target With my small group, I can find and check equivalent ratios using multiplication and division — one step at a time, with support.
Remember3.9 Small Group · Group 1
To make an equivalent ratio, multiply or divide both numbers by the same scale factor. The comparison stays the same. Equivalent ratios compare amounts in the same way. We make them by multiplying both numbers by the same scale factor.
Words: Equivalent Ratios (Razones equivalentes)Ratio (Razón)Rate (Tasa)Proportion (Proporción)Simplify (Simplificar)
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1Complete each step, then write the final answer.
A ratio is 3:4. Multiply both numbers by 5. The new ratio is 15 : ?. What is the missing number?
Show your workHint Multiply the second number by 5: 4 × 5.
Final answer: -
2Complete each step, then write the final answer.
A ratio is 5:2. Multiply both numbers by 4. The new ratio is 20 : ?. What is the missing number?
Show your workHint Multiply the second number by 4.
Final answer: -
3Complete each step, then write the final answer.
A paint color uses 4 cans of blue for every 5 cans of white. A painter uses 12 cans of blue. How many cans of white does the painter need?
Show your workHint Find the scale factor from 4 to 12. Use it on the white paint.
Final answer: -
4Complete each step, then write the final answer.
A ratio is 8:20. Find an equivalent ratio whose first number is 6. What is the second number?
Show your workHint No whole number times 8 makes 6. Divide both numbers first to make a smaller ratio.
Final answer:
Explain your thinkingJay added 2 to both numbers. Why must you multiply both numbers by the same number instead?
Sentence starter Adding 2 does not work because ___. · 2:3 and 4:6 are equivalent because ___.