SOLUTION: three quarters of a number is 21. find the number

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Question 54509This question is from textbook Algebra Structure and Method book 1
: three quarters of a number is 21. find the number This question is from textbook Algebra Structure and Method book 1

Found 2 solutions by rchill, josmiceli:
Answer by rchill(405) About Me  (Show Source):
You can put this solution on YOUR website!
Let x represent the number, then expr%283%2F4%29x is "three quarters of a number", and the equation becomes expr%283%2F4%29x=21. Now multiply both sides by 4 and get 3x=84 and dividing both sides by 3 yields x=28.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let x be the number
%283%2F4%29%2Ax+=+21
multiply both sides by 4
3x+=+84
divide both sides by 3
x+=+28
check by putting the answer back into the equation
%283%2F4%29%2A28+=+21
3%2A28+=+4%2A21
84+=+84
OK