Q10 of 47 Page 176

A works twice as fast as B. If both of them can together finish a piece of work in 12 hours, then B alone can do it in

Work done by A in one hour: 2x


Work done by B in one hour: x


Number of days taken by A and B to do the work together: 12 hours


Work done by A and B together in one hour:


= 2x + x


= 3x


X =


Here X is Work done by B in one hour


B alone will take 36 hours to complete the work.

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Fill in the blanks.

(i) A tap can fill a tank in 6 hours. The part of the tank filled in 1 hour is……………


(ii) A and B working together can finish a piece of work in 6 hours while A alone can do it in 9 hours. B alone can do it in ……….. hours.


(iii) A can do a work in 16 hours and B alone can do it in 24 hours. If A, B and C working together can finish it in 8 hours, then C alone can finish it in ……….. hours.


(iv) If A's one day's work is , then A can finish the whole work in……… days.