Answer is 30
How do I figure out how to get 30? I dont get it =(
If 45 is 120% of a number, what is 80% of the same number?
2008-12-16 2:58 pm
回答 (7)
2008-12-16 3:03 pm
✔ 最佳答案
Let x represent the unknown number.45 = (120/100)* x
x = (45)(100/120) = (225/6)
To get 80% of x, multiply:
(80/100)(225/6) = 30
2008-12-16 3:03 pm
45 ÷ 120%
= 45 ÷ 120/100
= 45 x 100/120
= 45 x 5/6
= 225/6
= 37.5
37.5 x 80%
= 37.5 x 80/100
= 37.5 x 4/5
= 150/5
= 30
= 45 ÷ 120/100
= 45 x 100/120
= 45 x 5/6
= 225/6
= 37.5
37.5 x 80%
= 37.5 x 80/100
= 37.5 x 4/5
= 150/5
= 30
2008-12-16 3:05 pm
PROPORTIONS:
x/100 = 45/120
x= (100 times 45)/120
x= 37.5 is the number
Now once again
37.5/100= y/80
y=( 37.5 times 80 )/100 = 30 is the answer
ANSWER
x/100 = 45/120
x= (100 times 45)/120
x= 37.5 is the number
Now once again
37.5/100= y/80
y=( 37.5 times 80 )/100 = 30 is the answer
ANSWER
2008-12-16 3:04 pm
Assume that 120 percent of X is 45
This means (120)(X) / 100 = 45
X = (100)(45) / 120
X = 37.5
120 percent of 37.5 is 45
We want 80 % of 37.5
=37.5 (80/100)
= 37.5 (0.8) = 30
This means (120)(X) / 100 = 45
X = (100)(45) / 120
X = 37.5
120 percent of 37.5 is 45
We want 80 % of 37.5
=37.5 (80/100)
= 37.5 (0.8) = 30
2015-11-13 11:34 pm
idk
2008-12-16 4:30 pm
120%<--------------->45
80%<------------->(80/120) x 45
2/3 x 45
2 x 15
30
80%<------------->(80/120) x 45
2/3 x 45
2 x 15
30
2008-12-16 3:06 pm
80% of number= 80/120*45=30
收錄日期: 2021-05-01 11:41:44
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081216065842AARb0TE