Kamille`s Percent Post

how to find key percents:
1.

a) to find 50 % of a number you have to divide the number by two.

b) to find 10 percent of a number you have to divid the number by ten.

c) to find 1% of a number you have to divide the number by one hundred.

d) to find 25% of a number you have to divide the number by four.

 A percent is number out of a hundred or a whole.

2.

180%

12 3/4 %

0.7%







3.
26% Decimal- divide it by 100 (26/100=0.26)
Fraction- make the numerator the numbers after the decimal and use the place value of the last number a decimal. (26/100)
Percent-take the decimal (0.26) multiply by one hundred (0.26x100=26%)



7/10 Decimal-divide the numerator by the denominator
 (7/10=0.7)
Fraction-make the numerator the number after the decimal (7) Then take the place value of the last number as a denominator (100) so, it's 7 over 100
Percent-multiply the decimal (0.7) by 100 (0.7x100=70%)


0.024 Percent-multiply decimal number by 100 (0.024x100=2.4%)
Decimal- divide the percent by 100 (2.4/100=0.024)
Fraction-take the numbers after the decimal except the zeros (2,4) for the numerator. For the denominator take the place value of the last number (1000) so it's 24 over 10000.

4. Mental math- 10% of 60=6, 10%of 60=6, 6+6=12
Calculator- 20% of 60- 20/100=0.2, 0.2x60=12

Mental math-1% of 100- 100/100=0.1, 40-100=0.4, 0.1/10=0.1, 0.4/10=0.04
Calculator- 0.1% of 40- 0.1/100=0.001, 0.001x40=0.04


Mental math- 100% of 400 =400, 100% of 400=400, 25% of 400= 100, 25% of 400= 100, 400+400+100+100=1000
Calculator- 250% of 499- 250/100=2.5, 2.5x400=1000


5. Question 7 on page 149: A herd of caribou was moved to a new location. The population increased by 10% the first year and then increased by 20% the second year.

a) find the population after the second year.

10/100=0.1
0.1x100=10
100+10=110

20/100=0.2
0.2x110=22
110+22=132

b) explain why there was not a 30% increase in population over the two years.

There was no 30% increase over th two years because the population wouldnt be precise. It would be a smaller amount than the actual pupolation with 10% increased the first year and 20% increased the second year combined.

30/100=0.3
0.3x100=30
100+30=130


Video about how to convert decimals to fraction :
Hope this helps you !(: