SOLUTION: 133 visitors visited a computer exhibition. 1/4 of the number of local visitors is equal to 3/7 the number of overseas visitors. How many local visitors and how many overseas visit

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: 133 visitors visited a computer exhibition. 1/4 of the number of local visitors is equal to 3/7 the number of overseas visitors. How many local visitors and how many overseas visit      Log On


   

Question 945803: 133 visitors visited a computer exhibition. 1/4 of the number of local visitors is equal to 3/7 the number of overseas visitors. How many local visitors and how many overseas visitors are there?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a = number of local visitors
Let +b+ = number of overseas visitors
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(1) +a+%2B+b+=+133+
(2) +%281%2F4%29%2Aa+=+%283%2F7%29%2Ab+
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(2) +7a+=+12b+
(2) +b+=+%28+7%2F12+%29%2Aa+
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by substitution:
(1) +a+%2B+%28+7%2F12+%29%2Aa+=+133+
(1) +%28+19%2F12+%29%2Aa+=+133+
(1) +a+=+%28+12%2F19+%29%2A133+
(1) +a+=+84+
and, since
(1) +a+%2B+b+=+133+
(1) +84+%2B+b+=+133+
(1) +b+=+49+
The number of local visitors is 84
The number of overseas visitors is 49
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(2) +%281%2F4%29%2Aa+=+%283%2F7%29%2Ab+
(2) +%281%2F4%29%2A84+=+%283%2F7%29%2A49+
(2) +21+=+21+
OK