Seven

Seven dwarfs will cut 420 stumps in 15 hours. After five hours, the two dwarves disappear discreetly. How many hours will the remaining dwarves complete the task?

Correct answer:

x =  14 h

Step-by-step explanation:

t=420/(7 15)=4    420=5 t 7+(72) x t 420=5 4 7+(72) x 4  20x=280  x=14 h



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