2006-11-01 03:26:03 · 18 answers · asked by LOST!~ 1 in Science & Mathematics ➔ Mathematics
The first thing to remember about percentages is that they represent a fraction who's denominator (bottom term) is 100 - for example, 40% is the same as 40/100 = 4/10 = 2/5. And the second is something I learned in math class about 40 years ago about percentage word problems - "percent" over "100" equals "is" over "of". Burn that into your brain. How do you use it? In your problem, "40" is the "percent", and "85" is the "of" (because it comes right after the "of"). So using the rule, your problem is:
40/100 = is/85
There's no "is" in you problem, therefore it must be the answer we have to solve for, right? So now you cross-multiply:
40*85 = 3400, and 3400/100 = 34, which is the answer.
What if your problem asked, "What percent of 85 is 34?"
34 is the "is" since it comes right after the word "is" in the problem, and 85 is still the "of" since it comes right after the "of", and since the problem asks "What percent...", percent is what we have to solve for. So using the rule, the problem sets up to:
percent/100 = 34/85
Now cross multiply again:
34*100 = 3400, and 3400/85 = 40, so 40 is the "percent", and therefore the answer! One more example: "34 is 40% of what?" This time, it looks like "of" is what we have to find, so the problem sets up to:
40/100 = 34/"of"
Cross multiply again:
100*34 = 3400, and 3400/40 = 85
See how easy percentage word problems are? Practice 30 problems like this, and don't forget that "percent over 100 equals "is" over "of", and remember how to cross-multiply.
GaryH
2006-11-01 04:17:54 · answer #1 · answered by Gary H 6 · 2⤊ 0⤋
40/100 multiplied by 85,ie 40/100*85=34
2006-11-01 04:21:13 · answer #2 · answered by Anonymous · 0⤊ 0⤋
40%=.4 so .4*85=34
2006-11-01 05:35:38 · answer #3 · answered by yupchagee 7 · 0⤊ 0⤋
100% =1
so 40% = 0.4
so 40% of 85 = 0.4 x 85 = 34
2006-11-01 03:59:54 · answer #4 · answered by grandpa 4 · 0⤊ 0⤋
(40/100)* 85
=35
2006-11-01 03:27:45 · answer #5 · answered by sunil 3 · 0⤊ 1⤋
Here is how I do it.
85 divided by 5 = 17
17 X 2 = 34
The answer is 34
2006-11-01 03:31:40 · answer #6 · answered by Alex 3 · 0⤊ 0⤋
.40 * 85 on your calculator!
2006-11-01 03:27:40 · answer #7 · answered by monie0078 2 · 1⤊ 1⤋
85/100=0,85x40=34
2006-11-01 03:27:59 · answer #8 · answered by apple_juice 2 · 0⤊ 1⤋
easy.... you multiply 85 x (.40)...... (.40) is the decimal for of 40%.... and if you wanted 4% of 85.... it would be..... 85x (.04)... good luck
2006-11-01 03:29:00 · answer #9 · answered by vinny 1 · 0⤊ 0⤋
mutiply 85 by .4
2006-11-01 03:27:57 · answer #10 · answered by sweetsmile 2 · 0⤊ 1⤋