Converting decimals to percents
Converting percents to Decimals.
Changing decimals to percents
Move the decimal place 2 positions to the right.
.357
= 35.7%
.5 = 50%
12.678
remember move 2 to the right.
we have to annex a 0 to have 2 places.
= 1267.8% - still only 2 places right
Your turn now:
.45
2.3
.09
.3
1
Changing percents to decimals is just the reverse.
Move the decimal place 2 places to the left.
Remember if there is no decimal showing, it is at the far right.
25% = 25.%
move 2 places left = .25
100% = 100.%
.05%
move 2 places left 1.00 or just 1
still move 2 places left .0005 must annex zeroes.
Your turn now.
13%
.03%
125%
15.8%
To change a percent to a fraction – place the
number over 100.
After all, per cent - means part of 100
Example 35% is 35/100 wait we have to
simplify
both 35 and 100 are divisible by 5 so the final
answer is 7/20
Your turn now.
15%
237%
125%
.05%
5%
13%
Change a fraction to a percent.
You must have a denominator of 100. If your denominator is
not 100, make an equivalent fraction with a denominator of
100.
The numerator is now the percent.
1/5
5 times 20 equals 100 so multiply both 1 and 5 by 20
5/100
remove the denominator 5%
You could also turn the fraction to a decimal and then change
the decimal to a percent.
1 ÷ 5 = .2 move decimal 2 places to right 20%
Your turn now.
2/5
1/3
3/8
3/4
Using Sage and Scribe method.
You will take turns working the
problems on the worksheet given to
you.
You will have until the timer rings.
Homework - page 417 16 – 30 evens only
You must copy these examples!
Examples: % to Fraction
example 1 82% = 82/100 divisible by 2 = 41/50
Fraction to %
example 2
13/25 must make it over 100
25 times 4 = 100 so multiply both 13 and 25 by 4
52/100 now remove the denominator
52%
example 3 13/25 13÷ 25 = .52 move 2 left 52%