SOLUTION: 1/a + 1/b = 1/c solve for b

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Question 849203: 1/a + 1/b = 1/c solve for b
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+1%2Fa+%2B+1%2Fb++=+1%2Fc+
+1%2Fb+=+1%2Fc+-+1%2Fa+
Multiply both sides by +b+
+1+=+b%2A%28+1%2Fc+-+1%2Fa+%29+
divide both sides by +1%2Fc+-+1%2Fa+
+b+=+1+%2F+%28+1%2Fc+-+1%2Fa+%29+
Multiply top and bottom of the right side by +a%2Ac+
+b+=+%28+a%2Ac+%29+%2F+%28+a+-+c+%29+
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To check, you can pick any numbers for a, and c.
Then find b
+a+=+11+
+c+=+7+
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+1%2Fa+%2B+1%2Fb++=+1%2Fc+
+1%2F11+%2B+1%2Fb++=+1%2F7+
+1%2Fb+=+1%2F7+-+1%2F11+
+1%2Fb+=+.1429+-+.0909+
+1%2Fb+=+.052+
+b+=+19.231+
and
+b+=+%28+a%2Ac+%29+%2F+%28+a+-+c+%29+
+b+=+%28+11%2A7+%29+%2F+%28+11+-+7+%29+
+b+=+77+%2F+4+
+b+=+19.25+
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I think it's correct, but +19.231+
and +19.25+ are a little far apart.
+19.25+ should be the right number.
You can recheck.