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At the moment, I am studying for my math exam. my teacher was nice enough to give us a study guide to fill out. I have a few things that I dont understand:
What is 39% of 500?
What percent of 64 is 3.2?
60% of 85 is what number?
What percent of 85 is 1.7?
What number is 150% of 26?
What i 40% of 400?
Not only do I not understand them, I dont know how to do them! So could someone PLEASE EXPLAIN ot me how to do them?
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Want to answer more questions in the Work & School category?
Maybe give some free advice about: School?
Here's an easy way to do it.
Translate an English sentence to a mathematical equation:
<b>What is 39% of 500?</b>
What number (unknown) = n (or another variable)
Is = well, =
39% = .39
of = multiply
500 = 500
So your equation would be
n = .39(500)
There's your example for those types of problems.
Now, for this one:
<b>What percent of 64 is 3.2?</b>
What percent = n
of = multiply
64 = 64
is = =
3.2 = 3.2
Your equation is
64n = 3.2
And for this type of problem:
<b>60% of 85 is what number?</b>
60% = .6
of = multiply
85 = 85
is = =
what number = n
Your equation is
85(.6) = n
It's really easy once you get the hang of it. I find it alot easier than setting up a porportion, even though you're really supposed to do it that way... >< But, this is a little way to "cheat" and do it the easy way.
I hope this helps you, it sure did help me out in math.
<3 Sporkster
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This may be very confusing!
For your first question:
put 39 over 100. Next to that put n over 500. Multiply 39 by 500. Now divide by 100.
You can do this whether you're trying to find a percent of something or you're trying to find what a percent of something is. Just switch where the N is in your problem and cross multiply and divide by the extra number.
I'm sorry if thats not what you were looking for!
PS- Good luck on your exam!
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yay math! (i have finals tomorrow)
make a preportion:
39%= 39/100, right? so 39/100 =X/500 Now cross multiply. 100X=(39)(500) so 100X=19500. Now devide each side by 100 to get the variable(X) alone. so X=195.
X% OF 64 = 3.2
Ok a little different, but same idea.
X/64= 3.2/100. now cross multiply. (64)(3.2)= 100X
204.8=100X. now divide by 100 so X= 2.048
hope i could help, try doing the others for practice and contact me if you have any more questions
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What is 39% of 500?
500 ×.39 = ___
- OR -
since you [ should ] know that 39% of 100 is 39, just do 500/100 = __[5]; & then 39 ×5 = ___
What percent of 64 is 3.2?
3.2/64 = ___
60% of 85 is what number?
85 ×.6 = ___
What percent of 85 is 1.7?
1.7/85 = ___
What number is 150% of 26?
26 ×1.5 = ___
or just do 26 + ( 26/2) = ___
What is 40% of 400?
400 ×.4 = ___
or 40 ×4 = ___
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Usually not understanding them, and not knowing how to do them are the same thing.
Just a head up for when you have to do your writing in english.
Repeating yourself is not good.
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I've learned this a few years ago so I'll tell you the formula, not the answers, to get the answers to the problems you've mentioned.
You need two set up to ratios/fractions so that the whole number or precent is the denominator and part of the number is the numerator. If you don't know what one number is, then replace it with an 'x'.
For example: The first problem would look something like x/500 multiplied by 39/100 ('x' is the missing number and 39/100 is the precent ratio.) Just cross multiply the two fractions so that you'll get 100x=19500 and divide and you'll get your answer, which is 195.
So basically, that's how you do each and every problem like that, but not with the exact numbers, just with the formula. I know that I've missed and didn't include everything so if you don't understand anything, ask your mathematics teacher.
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I used to have a huge problem with percents too, but here's how i do it:
39% of 500:
set up a ratio: 39/100 is ?/500. to get 500 from 100, you have to multiply by 5, so you have to multiply 39 by 5 to get the number, which is.. 195. so 39% of 500 is 195
40% of 400:
you can do this without using a ratio. if you divide 100 by 5, the quotient will be 20, multiply by 2 will give you 40, which is 40%. so you can try dividing 400 by 5, which gives you 80, and multiply by 2, which will give you 160.
you can also try diving the numbers by 10, or 2, or other numbers, but I think 5 is the easiest for this problem.
150% of 26:
if you turn 150% into a decimel, it will be 1.5. so 26 x 1.5 is 39, which is the answer. you could also try dividing 26 by 2 since 50% is 1/2, and the product will be 13. then you add 13 to 26 because it's asking for 150% of 26, and it'll give you 39.
there are many ways to work out percentages, but these are the only ways that I use. if you're still a little confused, just ask me for more help :)
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if you wanna find a percent just set up a proportion...theres a formula:
% over 100=is over of
so 39% of 500 is:
39 over 100 = x over 500, then just cross multiply and solve.
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im not going to tell you the answers because it wouldnt help you. but to do the first one and other ones that are like it. draw a rectangle box thing and on the top in the top 2 corners put 39% in the left top corner and 100% on the right top corner. then on the bottom 2 corners put x=the number you need to find and and in the right corner put 500. then divide 100/ 39 and you get a number then you divide 500 by that number so it would look like 500/x=(395%). that might be a little confusing but thats the best i can do. since its not on paper. hope i help. if i didnt help you enough then talk to your teachers or your parents or call a friend
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You should listen more in school to know this.And if i give you the answer that will not help you learn more.
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what you do is first put 39% over a 100 like a fraction then you put x over 500 like a fraction then you cross multiply then divide by 100x and voila there's yopur answer
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heyy .. im not sure how to do those myself and most people wont on here unless they have the same carriculum as you do but you could try asking your parents or guardian for some help or you could tell your teacher your not understanding a few questions to well and you need some help or you could search on the internet for some help like you know homework help and there is a calculater on computers that you can use to solve them
hope i helped
good luck
please rate
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