Math Worksheet - Grade 7 Page 33
ADVERTISEMENT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34th
7
Grade Honors
Unit: Knowledge of Number Relationships & Computation
T
Objective: Determine rate of increase and decrease, discounts, simple interest, commission, sales tax. - A
Examples:
• A percent of change is a ratio that compares the change in quantity to the original amount. If the
original quantity is increased, it is a PERCENT OF INCREASE. If the original quantity is decreased, it is
a PERCENT OF DECREASE.
Last year 2,376 people attended the rodeo. This year, attendance was 2,950. What was the percent of change in
attendance to the nearest whole percent?
n Since this year’s attendance is greater than last year’s attendance, this is a percent of INCREASE.
n The amount of increase is 2,950 – 2,376 = 574.
(Percent of DECREASE: original – new.)
amount
of
change
%
n
574
n Use the proportion:
n = 0.24 or 24%
=
=
original
amount
100
100
, 2
376
n The rodeo attendance increased by about 24%.
DISCOUNT
Determine the price of a $69.50 tennis racket that is on sale for 20% off.
20
n
n Use the percent proportion to determine the amount of discount.
20 x 69.50 = 100n
=
100
69
.
50
1390
= 100n
100
100
The amount of discount is $13.90
13.90 = n
n Subtract the amount of discount from the price.
69.50 – 13.90 = $55.60
The sale price of the tennis racket is $55.60.
1.) Determine the percent of change. Round to the
2.) Determine the sale price to the nearest cent.
nearest whole percent if necessary. State whether the
percent of change is an INCREASE or DECREASE.
$39.00 jeans
40% off
Original: 250
New: 100
3.) Determine the percent of change. Round to the
4.) Justin is buying a cell phone that has a regular price of
nearest whole percent if necessary. State whether the
$149. The cell phone is on sale for 15% off the regular
percent of change is an INCREASE or DECREASE.
price. What will be the sale price?
Original: $84
New: $100
5.) Alicia planted 45 tulip bulbs last year. This year she
**6.) You want to buy a new sweater. The regular price
plans to plant 65 bulbs. Determine the percent of increase
was $48 dollars. The sale price was $34. What was the
in the number of tulip bulbs to the nearest tenth.
percent of discount to the nearest percent.
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education