Transcript to Decimal

% to Decimal
% to Decimal
Just two steps. That’s
all it takes.
st
1 :
Remove the % sign.
This is the same exact thing
as multiplying by 100.
(x100)
2nd: Move the decimal two (2)
places to the left.
This is the exact same thing
as dividing by 100. (÷ 100)
Change 97% to decimal:
97%
1st:
97 (take away % sign).
2nd:
.97 (move invisible decimal point behind the
seven 2 places to the left in front of the 9).
Final answer = .97
Change 461% to decimal:
461%
1st:
461 (take away % sign)
2nd:
4.61(move invisible decimal point from
behind the 1 two places to left so it is in
between the 4 and the 6)
Final answer = 4.61
Change 1350% to decimal:
1350%
1st:
1350 (take away the % sign)
2nd:
13.50 (move the invisible decimal point
behind the 0 two places to the left so it is
between the 3 and the 5).
Final answer = 13.50 or 13.5
Change 7% to decimal:
7%
1st:
7 (take away the % sign
2nd:
.07 (move the invisible decimal point behind
the 7 two places to the left. Fill in the
empty spot this made with a zero. The
decimal place is now in front of the new 0).
Final answer = .07
Change .09% to decimal:
.09%
1st:
.09 (Take away the % sign, but leave the decimal
point where it is during this step.)
2nd:
.0009 (Move the decimal point from in front of the
0 two places to the left. This creates 2 empty
spaces. Fill them with 2 new 0s. Now the
decimal point is in front of 3 zeroes.
(1 original 0 & 2 new 0s)
Final answer = .0009
Change .3468% to decimal:
.3468%
1st:
.3468 (take away the % sign)
2nd:
.003468 (move the decimal place 2 places
to the left. This creates 2 empty spaces.
Fill them with 0.)
Final answer = .003468
Change ½ % to decimal:
New 1st step:
Change fraction to decimal first.
½ = .50 or .5
__.5___
2) 1.0
So: ½ % = .50%
10
Now rewritten problem:
0
Change .50% to decimal:
Change .50 % to decimal:
(Note: This is NOT (fifty) 50 %, it is (five tenths) 5/10 %
or when the fraction five tenths is simplified
(one half) ½ %)
.50 %
1st:
.50 (take away the % sign)
2nd:
.0050 (move the decimal point 2 places to the left)
Final answer = .0050 or .005
2 ways to write
the exact same numbers
97% is the exact same amount as .97
461% is the exact same as 4.61
1350% is the exact same number as 13.50
7% is the exact same as .07
.09% is the exact same amount as .0009
.3468% is the exact same as .003468
½ % is identical to .5 % and .50% and .0050
% and decimals are equivalent
Doing BOTH the
1st step: Remove the % sign (x 100)
and the
2nd step: Move the decimal point two places
to the left (÷ 100)
is multiplying the percent by 1 or (100).
(100)
Multiplying any number by 1 equals the
exact same number you started with.
So multiplying a percent by 100 equals the
100
exact same number and the exact same
amount you started with,
but the number is
written as a decimal instead of a percent.
Congratulations
Now you know how to change a number
from a percent to a decimal
by simply
removing the % sign
and
moving the decimal point 2 places to the left.
Notes for teachers
Correlates with Glencoe Mathematics Applications and
Concepts : Course 1 Florida Edition (6th grade) Chapter
10 Lesson 6
Glencoe Mathematics Applications and Concepts : Course
2 Florida Edition (7th grade) Chapter 5 Lesson 6
Glencoe Mathematics Pre-Algebra Florida Edition (8th
grade) Chapter 6 Lesson 4
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