document.write( "Question 1127607: At one store, 5 pairs of jeans and 2 sweatshirts costs $213, while 3 pairs of jeans and 4 sweatshirts costs $195. Find the cost one sweatshirt. \r
\n" ); document.write( "\n" ); document.write( "A. $21
\n" ); document.write( "B. $35
\n" ); document.write( "C. $33
\n" ); document.write( "D. $24 \n" ); document.write( "

Algebra.Com's Answer #744068 by MathTherapy(10553) $\"\"$ $\"About$

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At one store, 5 pairs of jeans and 2 sweatshirts costs $213, while 3 pairs of jeans and 4 sweatshirts costs $195. Find the cost one sweatshirt. \r
\n" ); document.write( "\n" ); document.write( "A. $21
\n" ); document.write( "B. $35
\n" ); document.write( "C. $33
\n" ); document.write( "D. $24
\n" ); document.write( "

Never do a problem like this the way the other person did. It's an extremely inefficient, very time-consuming, and error-prone way to solve a SIMPLE system-in-2-variable equation.\r
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document.write( "Let cost of a pair of jeans, and a sweatshirt be J, and S, respectively
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document.write( "Then we get: 5J + 2S = 213 --- eq (i)
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document.write( "Also, 3J + 4S = 195 ---------- eq (ii)
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document.write( "   - 10J - 4S = - 426 -------- Multiplying eq (i) by - 2 ------ eq (iii)
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document.write( "         - 7J = - 231 -------- Adding eqs (iii) and (ii)
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document.write( "J, or cost of a pair of jeans = 
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document.write( "5(33) + 2S = 213 ------ Substituting 33 for J in eq (i)
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document.write( "165 + 2S = 213
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document.write( "2S = 213 - 165
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document.write( "2S = 48
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document.write( "S, or cost of a sweatshirt = 
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document.write( "That's all!! Again, never follow anyone who advises you to do it the way she did, with those MONSTROUS fractions. Who wants to deal with those???
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document.write( "I can't believe these people are claiming to be helping others. Is this really help? \n" );
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