Name___________________
Date______
Period_______
Chapter 6
Learning Targets
Learning Targets
• #1: I can change fractions to decimals and
percents.
B: 1 2 3
I have these questions:
A: 1 2 3
To Change A …
LT #1
Fraction To a Decimal:
3
4
Example: Change to a decimal.
Divide the numerator by the denominator.
3
4
=
3 4
=
75
4 300
-2 8
13
42 0
-2 0
0


SO: 43
.75
=
Fraction To a Percent: Example: Change to
1
4a
percent.
If possible, find an equivalent fraction that has a
denominator of 100.

1 25
?
25


Per-cent means per 100

4 25
100
100
 25%
Learning Targets
• #2: I can change decimals to percents and
fractions.
B: 1 2 3
I have these questions:
A: 1 2 3
LT #2
Decimal to a Percent: Example: Change .34 to a percent
Multiply the decimal by 100.
.34 • 100 = 34%
Decimal to a Fraction: Example: Change .2 to a fraction
Read the decimal using the correct place value. How
you say it determines the fraction. Reduce.
“
0.2  2  1
Two-tenths
”
10
5
Learning Targets
• #3: I can change percents to decimals and
fractions.
B: 1 2 3
I have these questions:
A: 1 2 3
LT #3
To Change a …
Percent to a Decimal : Example: Change 27.5% to a
decimal.
Change the percent to a fraction then divide.
27.5%

275
27.5 100 27 500
=
=
-200
100
750
700
500
500
0
Example #2: Change 39% to a decimal.
39% =
39
100
=
.39
Learning Targets
• #3: I can change percents to decimals and
fractions.
I have these questions:
LT #3
To Change a …
Percent to a Fraction : Put 100 in the
denominator and reduce if possible.
Example #1: Change 42% to a fraction.
42 2
21
42% 

50
100 2

Example #2: Change 35.5% to a fraction. Put 100 in the
denominator and multiply by a power of 10 Giant One to
get rid of decimals in the numerator. Reduce if possible.
35.5% = 35.5 10
100 10
355 5

1000 5
71

200
Learning Targets
• #4: I have memorized these benchmarks.
B: 1 2 3
I have these questions:
A: 1 2 3
Lt #4
5%
10%
= .05
= .1
20% = .2
25% = .25
=
1
20
=
1
10
=
=
1
5
1
4
33.3%
50%
=
66.6%
75%
=
.3
=
.5
=
=
.6
.75
=
1
2
=
=
1
3
3
4
2
3
Learning Targets
• #5: I can use benchmarks and shortcuts to
estimate percents.
B: 1 2 3
I have these questions:
A: 1 2 3
LT #5
1.
2.
3.
4.
5.
250
What is 50% of 500? ____
What is 25% of 500? ____
125
What is 10% of 500? ____
50
What is 5% of 500? ____
25
What is 1% of 500? ____
5
1) 8% of 500
8% = 10% – 2%
= 50 – 10
= 40
2) 61% of 500
61% = 50% + 10% + 1%
= 250 + 50 + 5
= 305
Learning Targets
• #5: I can use benchmarks and shortcuts to
estimate percents.
I have these questions:
LT #5
Estimate:
21% ≈ 20%
66 rounds to 70
New, easier problem:
20% of 70
21% of 66
Use a benchmark close to 21%.
Round 66 to nearest 10.
New problem is 20% of 70.
Use mental math: 20% of 70 =
10% + 10% =
7 + 7 = 14
So 21% of 66 is about 14.
Learning Targets
• #6: I can solve percent problems.
B: 1 2 3
I have these questions:
A: 1 2 3
Lt #6
Solving Percent Clues
1) First locate the %
2) Then find the is and of
3) Or find the part and the whole (in
some cases, the part might be bigger than the whole!)
is %
=
of 100
or
part
%
=
whole 100
LT #6
50 is what % of 200?
“is” = 50
% = unknown (p)
“of” = 200
50
p

200 100
part
%
=
whole 100
(100)
50
p

200 100
1) Identify the %, the
is, and the of.
is %
=
of 100
(100)
2) Write the
proportion
3) Solve
(100)50
p
200
p  25%
Fifty is 25% of 200.
LT #6
What is 30% of 70
“is” = unknown (a)
% = 30
“of” = 70
a
30

70 100
(70)
a
30

70 100
(70)
is
%
=
of 100
1) Identify the %, the
is, and the of.
2) Write the
proportion
3) Solve
30(70)
a
100
a  21
Twenty one is 30% of 70.
LT # 6
10 is 25% of what # ?
% = 25
is = 10
“of” = unknown (b)
10 25

b 100
(10) b  100 (10)
10
25
(10) b  100 (10)
10
is %
=
of 100
1) Identify the %, the
is, and the of.
2) Write the
proportion
25
1000
b
25
b = 40
3) Solve
Ten is 25% of 40.
Learning Targets
• #6: I can solve percent problems.
I have these questions:
LT #6
Convert Percent to a Decimal
39% of 60 =
60 = 23.4
.39
5
0.39
x 60
0 00
23 4 0
23 4 0
LT #6
Example % of Number
A $70 skateboard was discounted 17%. How much
was it discounted and what was the new price?
Discount amount
17% of $70
.17  $70
$11.90
New Price = original price – discount amt.
$70.00
-
$11.90
$58.10
The discount is $11.90 and the new price is $58.10.
LT #6
Find the amount of the discount and
the new price if a $31.25 toy is
discounted 33%.
$31.25 toy discounted 33%
Find 33% of $31.25
0.33  $31.25
(Round to
 $10.3125 nearest cent)
 $10.31 discount
The discount was $10.31 and the new price is $20.94
New Price
$31.25
-10.31
$20.94
Learning Targets
• # 7: I can find percent discounts.
B: 1 2 3
I have these questions:
A: 1 2 3
LT # 7
Percent Discount
A $28 book is on sale for $21. Find the % discount.
Percent Discount
Percent Change
From $28 to $21
Disc
ount
%
Original Amount
%
Discount
Original Amount
=
%
$7
$28 =
.25
Now change decimal
to a percent
25% Discount
The percent discount is 25%.
Learning Targets
• # 8: I can calculate sales tax.
B: 1 2 3
I have these questions:
A: 1 2 3
LT #8
Sales Tax
A family purchased a DVD player for
$200. The sales tax rate was 7%. What
was the total cost of the purchase?
Method 1
Method 2
Add sales tax to the price:
Multiply the price by 107%
since 7% is added to the cost.
$200  7% = tax
$200  .07 = $14.00 tax
$200 + 14.00 = $214.00
$200  107% = total cost
$200  1.07 = $214.00
So, the total cost was $214.00.
Learning Targets
• # 9: I can calculate tips.
B: 1 2 3
I have these questions:
A: 1 2 3
Tips
LT #9
Mrs. Girt earned average tips of 18% while waiting
tables at Denny’s. If her sales one night
were $730, what did she make in tips?
2
730
x 0.18
15 8 4 0
7 30 0
13 140
Tips  18% of 730
Tips = 0.18
730 = $131.40
Mrs. Girt earned $131.40 in tips that night.
LT #9
Tips
The dinner bill at Olive Garden was $58.57 cents. If your family
wanted to leave a 15% tip for the waiter approximately how much
should they leave?
Tip = 15% of $58.57
Tip = .15
58.57
Use Benchmarks and Short cuts to estimate tip:
Round $58.57 to $60 then take 15% by using 10% + 5% to get the tip.
10% of $60 = $6
+ 5% of $60 = $3
15% of $60 = $9
So the tip should be about $9.
Learning Targets
• # 10 : I can calculate simple interest.
B: 1 2 3
I have these questions:
A: 1 2 3
LT #10
INTEREST, PRINCIPAL, RATE
Interest Rate: the amount paid for the use of
money. You owe interest if you borrow money.
You can make interest by putting money in a
savings account at a credit union or bank.
Principal: the amount of money you borrow or
deposit (put into an account).
Time: the time (in years) that the money is
borrowed or saved.
Simple Interest : interest that is paid only on
the original amount of the principal.
LT #11
SIMPLE INTEREST
Dylan has $500 in a savings account. The
bank pays 5% simple interest.
How much interest will he earn in 2 years?
Simple Interest = Principal Rate Time
I  P r t
I  (500) (0.05) (2) r  5%  0.05
I  $50
The interest earned is $50.
The total in the account is $550:
$500 principal plus the $50 interest.
LT #1 1
SIMPLE INTEREST
John gets a loan from the bank for $2,500 dollars to buy his
first car. The bank charges him 6% simple interest on the 5
year loan. How much total interest will he be charged and
what will be his total repayment amount?
Simple Interest = Principal Rate Time
I  P r t
I  2500 (.06)(5)
rate = 6% = .06
I =$750
The interest he owes the bank for using their money is $750.
The total John owes the bank for using their money is
Principal + Interest = $2500 + $750 = $3250