Percent means...
Percent s a equivalent fraction that's out of 100.
They picked 100 to be percent because 100 is the right number that's not too big and not too small.
the word percent and symbol % both meant out of 100, PER = out of, and CENT = 100. % = /100.
Here is how we find %,
we can use a T chart to find the %,
for example,
we have 60 pencils,
what is 10% of 60?
what is 25 % of 60?
what is 50 % of 60?
PERCENT | PENCILS
100 | 60
/10 | /10
10 | 6
PERCENT | PENCIL
100 | 60
/4 | /4
25 | 15
PERCENT | PENCIL
100 | 60
/2 | /2
50 | 30
Representing Percent
a)180%
b)0.6%
c) 12 3/8
fraction -- decimal -- percent
88/50
88/50 = 1.76
because 88 divide by 50 equals = 1.76,
1.76/1 * 100/100 = 176/100 or 176%
decimal -- percent -- fraction
0.0064 * 100 = 0.64 or .64%
0.0064 = 64 /10 000
64 16 4
--- / ---- = ---
10000 16 625
percent -- decimal -- fraction
0.3%
0.3 / 100 = 0.003
0.003 = 0.003 / 1000
0.003 = 3 / 1000
understanding percent,
combining percents,
decimal, fraction
4.10% = 6
because, you move the decimal 60. to the left once,
10 x 2=20
6 x 2=12
calculation:
20/100
0.20 x 60 = 12
2)0.1% of 40
0.1 x 1000 =100
40/1000 = 0.04
calculation:
0.001 x 40 = 0.04
3)250% of 400
250 x 400 = 100000
100000 / 100 = 1000
calculation:
250/100 = 2.5
400 x 2.5 = 1000
5.
Tips: % OFF = discount,what you save
sale price = what you pay
question 7 from pg. 149 (text book)
A herd of 100 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.
first year:
10 + 100 = 110
110 100 1.1
--- / --- = --- = 1.1
100 100 1
1.1 X 100 = 110
OR
10% of 10010% + 100% = 110%
110/100 = 1.1
1.1 x 100 = 110
110 caribou
20 + 100 = 120
120 100 1.2
--- / --- = --- = 1.2
100 100 1
1.2 X 110 = 132
OR
20% of 110
20% + 100% = 120 %
120 / 100 = 1.2
1.2 x 110 = 132
The population after the second year is 132.
b) Explain why there was not a 30% increase in population over the two years.
There was not a 30% increase in population over
two years because, the percent had changed. we
need to find 10% of 100 first, when we get the
answer we have to find 20% of that number.The
number had changed, we are not looking for the
percent of 100 so, the final answer would
change too.
SHOW YOU KNOW ....
What is the final sale price at each store? Which is a better buy?
Explain your thinking.
Store A: 50% off one day only
Store B: 25% off one day followed by 25% off the reduced price the
second day
For Example
The total price of the jacket is 200 dollars
store a)
50% off means half off
half of $200 is $100
OR
50% = 0.5
0.5 X 200 = $100
store b)
the first day...
75% = 0.75
0.75 X 200 = $150
OR
25% of 200 = 50
200 - 50 =$150
the second day...
75% = 0.75
0.75 X 150 = $112.5
OR
25% of 150 = 37.5
150 - 37.5 = $112.5
The final price for store a) is $100, and for sore b) is $112.5. Store a) is a better choice because, store a) is 50% off which means it is half of the regular price. Store b) is 25% off from the regular price, and 25% off from the reduced price, the number had changed smaller so, the discount would change smaller too. If the discount gets less then, the sale price gets more.
convert percents, decimals and fractions....
No comments:
Post a Comment