SOLUTION: One number is 4 times another. If the sum of their reciprocals is 5/12 find the two numbers.

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Question 107366: One number is 4 times another. If the sum of their reciprocals
is 5/12 find the two numbers.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Call the numbers a and b
a+=+4b
1%2Fa+%2B+1%2Fb+=+5%2F12
multiply both sides by ab
b+%2B+a+=+%285%2F12%29%2Aab
b+%2B+4b+=+%285%2F12%29%2A4b%2Ab
5b+=+%285%2F12%29%2A4b%5E2
5+=+%285%2F12%29%2A4b
4b+=+%2812%2F5%29%2A5
4b+=+12
b+=+3answer
a+=+4b
a+=+12answer
check
1%2Fa+%2B+1%2Fb+=+5%2F12
1%2F12+%2B+1%2F3+=+5%2F12
1%2F12+%2B+4%2F12+=+5%2F12
5%2F12+=+5%2F12 OK