Percent Problems: Discounts, Tax and Tips

SubstitutePlans.com
Mathematics · Math 6-7
SP-MATH68-004 · Free to print and use in your classroom · substituteplans.com
Page 2
Percent Problems: Discounts, Tax and Tips
Mathematics · Math 6-7 · Grades 7 · 50 minutes
Time needed
50 minutes (one class period)
Prep
Copy the 2-page worksheet (one per student). Write the percent shortcuts on the board.
Technology
None. Calculators are optional for arithmetic only.
Student
independence
High. Students work alone, then compare with a partner.
Copies to make
One 2-page worksheet per student
Materials
Pencils, Worksheet, Whiteboard or chalkboard
Goal for today: Students will find a percent of a number, compute discounts, tax and tips, and find what percent one
number is of another.
Before the bell
☐ Copy the worksheet, one per student (2 pages).
☐ Write on the board: “10% of a number = move the decimal one place left. 50% = half. 25% = one quarter.
For 15%: find 10%, find half of that (5%), and add.”
☐ Keep the answer key on your desk. You do not need to solve anything yourself.
Say this to start
Good morning! Today is all about percents in real life: sales, tax and tips. Your worksheet starts with a matching game
and then moves to problems. The shortcuts are on the board. Do the work on your own first, and we will check answers
near the end of class.
Run of show
Minutes
What you do
What students do
0–5
Take attendance the way the school requires. Hand out the
worksheet face down and ask students to wait.
Settle in, take out a pencil, and wait for
directions.
5–12
Read the board shortcuts aloud. Work one example
together: 10% of 80 is 8, so 20% of 80 is 16. Ask, “What is
5% of 80?” (4)
Follow along and answer aloud.
12–20
Tell students to complete the matching section (questions
1–6).
Match each percent to its fraction.
20–35
Tell students to complete questions 7–13. Walk the room. If
a student is stuck, ask, “Are you finding the percent OF the
price, or what is left after?”
Solve the percent problems and show the
work.
35–45
Tell students to do the Error Detective table and questions
14–15. Then read the answers for questions 1–13 aloud
from the key. Students mark each one right or wrong.
Finish the last section and check their work.
45–50
Remind students to finish question 15 (the last line). Then
collect all worksheets.
Write one sentence for question 15. Hand
in the worksheet.

SubstitutePlans.com
Mathematics · Math 6-7
SP-MATH68-004 · Free to print and use in your classroom · substituteplans.com
Page 3
If things go wrong
• If students say, “We have not learned this,” tell them it is practice and the example on the board shows every
step. Pair them with a neighbor who is comfortable.
• If a student subtracts the percent as a plain number (40 − 30), remind them: 30% is a part of $40, so find
30% of 40 first.
• If a student finishes in under 20 minutes, check the sale-price steps, then use the early finisher list.
• If the class is noisy, remind them it is quiet individual work time.
Early finishers
• Make up a sale problem with an original price and a percent off. Solve it and trade with a neighbor.
• Find a 15% tip and a 20% tip on a $30.00 bill. Which costs more, and by how much? (Answer: $4.50 and
$6.00; $1.50 more.)
Support and challenge
• Support: Let students use a calculator for arithmetic only. Ask them to complete questions 1–6, 7, 9 and 11.
• Challenge: Ask students to find the original price of an item that costs $60 after a 20% discount. (Answer:
$75.)
Notes for the teacher (you fill this in)
Jot a few lines before you leave. A full Daily Sub Report is in the free Sub Survival Kit at SubstitutePlans.com.
How far the class got / what to pick up next:
Students who were especially helpful:
Anything the teacher should know: