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A can do s piece of work in 'x' days and B can do the same work in (x + 16) days. If both working together can do it in 15 days. Calculate 'x' |
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Answer» do a piece of work in X DAYS and B do work in x+16 daysThen A one day work = x1 daysAND B one day work = x+161 daysThen Both one day work = x1 + x+161 = x(x+16)x+16+x = x 2 +16x2x+16 So both do work in 2x+16x 2 +16x days But both do work in 15 days∴ 2x+16x 2 +16x =15⇒x 2 +16x=30x+240⇒x 2 −14x−240=0⇒x 2 −24x+10x−240=0⇒x(x−24)+10(x−24)=0⇒(x−24)(x+10)=0Then x−24=0,x=24And x+10=0,x=−10But work done is not negativeThen work done =24 days |
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