Lesson 4: Find and Compare with Percentages6.AT.4

I can…

I can find the percent of a number using an equation or a model.

Key words

• Percent of a Number — The piece of a number that the percent names.
• Percent — A number out of 100, shown with the % sign.
• Base — The number you take the percent of.
• Part — A piece of the whole.
• Equation — A math sentence with an equal sign.
• Discount — Money taken off a price.
• Double number line — Two number lines side by side. Marks that line up go together.
• Equivalent fraction — Fractions that name the same amount.

Steps

1. The claw machine costs 60 tickets, and it is 25% off. I need 25% of 60.
2. Step 1 — find the base (the whole): the number after “of” is 60.
3. Step 2 — the percent as a decimal: 25% means 25 out of 100, so 25 ÷ 100 = 0.25.
4. Step 3 — multiply: 0.25 × 60 = 15.
5. The discount is 15 tickets. Check: 15 is about a quarter of 60, so that makes sense.

Try it

What is 35% of 260?

Check your answer

91

35% = 0.35. Multiply: 0.35 × 260 = 91. A student who answers 35 wrote the percent number itself instead of finding the part. A student who answers 225 subtracted the percent number from the base (260 − 35) instead of multiplying. A student who answers 130 rounded 35% up to 50% before multiplying (0.50 × 260). Always convert the exact percent to a decimal, then multiply by the base.

Sentence starter

I know ___ because ___.

Goal: I can explain my steps using the words percent, base, part, and equation.