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An alternative method would be to use proportions (it is the same thing as post #2 just in a different form).

38, "a" is what percent of 216, "b"? :

First write your two numbers as a fraction: 38/216.

Now, a percent is what fraction of 100 a number is, so you can write what percent 38 is of 216 as a fraction: x (whatever percent of 216 38 is)/100

So now you have: x/100.

So 38 is the same ratio to 216 as x is to 100 so you can set the two expressions equal: 38/216 = x/100.

Now you solve the equation:

38/216 = x/100

100(38/216)=100(x/100)

3800/216=(100/100)x

17.5925... = (1)x

17.5925....=x

So, 38 is approximately 17.5926% of 216.

If you wish, you can check your answer.

Take your percent (17.5926) and divide it by 100: 17.5926/100 = .175926

Now multiply this number by the denominator of your other fraction (that is "b" in the expression "find the percent a of b"), so in this instance we would have (.175926)(216).

If you set your proportion up correctly, this should equal "a" :

(.175926)(216)= 38.000016.

This is 0.000016 different than what you should get. This error is due to rounding, if you carried the decimals in 17.5925... to infinity, then you would get exactly 38.

Since 38 = a, the solution "checks".

More generally, if you wish to know what percent, "x", "a" is of "b", then just set up and solve the proportion : a/b = x/100.

x will be your answer.

**goteamusa**- Replies: 3

I have read a little about busy beaver functions, but I do not really understand how they work. I know it has to do with the number of steps Turing machines will run until they halt, but I do not understand where the answers come from!? What calculations are being performed? Also, why do the numbers grow so large so quickly? Can this be explained so that it is easy to understand? Thanks.

**goteamusa**- Replies: 0

I am currently a sophmore in college. I took Calc 2 in 12th grade, and I am currently enrolled in Intro to Theoretical Mathematics. I plan on taking Calc 3 next semester. Is there anything specific that I should (can) do to prepare? Thanks.

**goteamusa**- Replies: 2

Hi! I am really looking forward to being here - I love math and this looks like a fun and wonderful forum!

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