math help plz show me how you did it and the answer?

Question

everyday,on average,11,318 American youth(12to20years of age) try alcohol for the first time,compared with 6,488 for marijuana;2,786 for cocaine;and 386 for heroin.Of those who try illegal substance(total),what percent try:Alcohol? Marijuana? Cocaine? And Heroin?(give all answers 2 each and how you did it)

Answer 1

add all together
386 Heroin
2786 Cocaine
6488 Marijuana
11318 Alcohol
----------
20978 total

now divide each
387/20978=.02 or 2%
2786/20978=.13 or 13%
6488/20978=.31 or 31%
11318/20972=.54 or 54%

Then add all % to make sure they add 100%
2%+13%+31%+54%=100%

Answer 2

Add the figures for each to find out the total number of people.
Divide the figure for alcohol by the total, and multiply the answer by 100 to get the percent.

Note: to remember which number goes first when you divide, think "out of". Example 2 out of 4 kids procrastinate on their homework. Use "divided by" for the "out of". 2 divided by 4.

11318 + 6488 + 2786 + 386 = 20978

In this problem 11,318 out of the total 20,978 tried alcohol.
So it's 11,318 divided by 10,978.

11318 / 20978 = 0.5395
0.5395 * 100 = 53.95% or 54%

Do the same for the other answers.

Answer 3

Add up all of the numbers. Then divide that number by each of the individual ones and multiply by 100. It's really just fractions.

Answer 4

add 11,318+ 6488+ 2786+ 386
and that adds to 20978

divide 11318 by 20978 and get .5395 and move decimal point 2 spaces to the right and get 54% or more specifically 54.1%
divide 6488 by 20978 and get .30928 and move decimal point 2 spaces to the right and get 31% or more specifically 31.3%
divide 2786 by 20978 and get .1328 and move decimal point 2 spaces to the right and get 13% or more specifically 13.3%
divide 386 by 20978 and get .0184 and move decimal point 2 spaces to the right and get 2% or more specifically 2.04%.

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