document.write( "Question 1147215: Can you please help me find the formula for this question?
\n" ); document.write( "A jet left Singapore five hours before a passenger plane. The planes flew in opposite directions. The passenger plane flew 315 mph for four hours. After this time the planes were 5670 miles apart. What was the jet's speed?
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Algebra.Com's Answer #768576 by MathTherapy(10553)\"\" \"About 
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Can you please help me find the formula for this question?
\n" ); document.write( "A jet left Singapore five hours before a passenger plane. The planes flew in opposite directions. The passenger plane flew 315 mph for four hours. After this time the planes were 5670 miles apart. What was the jet's speed?
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Let the jet's speed be S
\n" ); document.write( "The plane flew for 4 hours at 315 mph, or a distance of 4(315) = 1,260 miles
\n" ); document.write( "When the plane had flown 1,260 miles, the jet had flown 9 (5 + 4) hours, and 9S miles
\n" ); document.write( "When the jet had traveled 9S miles, and the plane 1,260 miles, the sum of their distances was 5,670 miles
\n" ); document.write( "We then get: 1,260 + 9S = 5,670
\n" ); document.write( "9S = 5,670 - 1,260
\n" ); document.write( "9S = 4,410
\n" ); document.write( "S, or jet’s speed was: \"highlight_green%28matrix%281%2C4%2C+%224%2C410%22%2F9%2C+%22=%22%2C+490%2C+mph%29%29\" \n" ); document.write( "
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