document.write( "Question 1146599: The resistance R of two resistors in parallel is given. R is found to be 283.0 Ω, but if R1 is doubled and R2 halved, then R is found to be 291.0 Ω. Find R1
\n" ); document.write( "and R2\r
\n" ); document.write( "\n" ); document.write( "1/R = 1/R1 + 1/R2 \n" ); document.write( "
Algebra.Com's Answer #767879 by Alan3354(69443)\"\" \"About 
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The resistance R of two resistors in parallel is given. R is found to be 283.0 Ω, but if R1 is doubled and R2 halved, then R is found to be 291.0 Ω. Find R1
\n" ); document.write( "and R2
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\n" ); document.write( "R1*R2/(R1+R2) = 283 ------------- Eqn 1
\n" ); document.write( "R1*R2/(2R1 + R2/2) = 291
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\n" ); document.write( "R1*R2 = 283(R1+R2)
\n" ); document.write( "R1*R2 = 291*(2R1 + R2/2)
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\n" ); document.write( "283(R1+R2) = 291*(2R1 + R2/2)
\n" ); document.write( "283R1 + 283R2 = 582R1 + 145.5R2
\n" ); document.write( "137.5R2 = 299R1
\n" ); document.write( "R1 = 137.5R2/299
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\n" ); document.write( "Sub into Eqn 1
\n" ); document.write( "(137.5R2^2/299)/(137.5R2/299 + R2) = 283
\n" ); document.write( "(137.5R2^2/299)/(137.5R2/299 + 299R2/299) = 283
\n" ); document.write( "(137.5R2^2)/(137.5R2 + 299R2) = 283
\n" ); document.write( "(137.5R2^2)/(137.5R2 + 299R2) = 283
\n" ); document.write( "(137.5R2)/(137.5 + 299) = 283
\n" ); document.write( "137.5R2/436.5 = 283
\n" ); document.write( "137.5R2 = 123529.5
\n" ); document.write( "R2 = 898.4 ohms
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\n" ); document.write( "Solve for R1, take a break
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\n" ); document.write( "PS R2 is not a standard value. 910 ohms is the closest standard value.
\n" ); document.write( "It has to be special ordered.\r
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