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7th grade · Math · Unit 9 of 18

Percents & Proportions

Increase, decrease and proportional

What your child practices

Knowing common fraction, decimal and percent equivalents, increasing and decreasing numbers by 1%, 5%, 10%, 25%, 50% and 100%, and deciding whether a relationship is proportional.

Alabama Course of Study content standard: 7.2; 7.3 · proportional relationships and multi-step percent problems

How we explain it

Children can open this short lesson before they practice.

  1. Know common matches: 1/2 = 0.5 = 50%, 1/4 = 0.25 = 25%.
  2. To increase by a percent, multiply by 1 plus the percent as a decimal.
  3. A proportion says two ratios are equal.

Example: Increase 80 by 25%. 25% of 80 = 20. 80 + 20 = 100. Answer: 100

Percents & Proportions in Alabama

In the Alabama Course of Study, this is unit 9 of 18 in 7th grade Math, after Fractions and before Algebra Moves.

Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.

Source: Alabama State Department of Education (ALSDE)

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Which fraction is equal to 20%?

    • 7/10
    • 2/5
    • 1/5

  2. Question 2

    Decrease 200 by 5%. What is the new number?

    answer box

  3. Question 3

    What number makes these ratios equal?

    2 : 6 = 10 :

    answer box

  4. Question 4

    5 notebooks cost $8.65. At the same price, how much do 8 notebooks cost, in dollars?

    answer box

  5. Question 5

    A taxi charges $4 to start, plus $2 for every kilometer. Is the cost proportional to the distance?

    • No, there is a starting fee
    • Yes, because the starting fee is small
    • Yes, because it goes up by $2 each time

  6. Question 6

    Which decimal is equal to 3/20?

    • 0.2
    • 0.15
    • 0.05

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