A man starts climbing a 11 m high wall at 5 pm. In each minute he climbs up 1 m but slips down 50 cm. At what time will he climb the wall?
A. 5:30 pm
B. 5:21 pm
C. 5:25 pm
D. 5:27 pm
Answer: Option B
Solution(By Examveda Team)
1st Method: Man climbs 1m and slips down 50 cm (0.5m) in one minute i.e. he climbs (1 - 0.5 = 0.5 m) in one minute. But in the last minute he will be climbing 1m as he gets on the top so no slip. Time taken to climb 11 meter = $$ {\frac{{10}}{{0.5}} + 1} $$ = 21 minutes. He climbs the wall at 5:21 pm 2nd Method (short-cut): $$ = \frac{{{\text{hight}}\,\,{\text{of}}\,\,{\text{pole}} - {\text{slipped}}\,\,{\text{distance}}}}{{{\text{climbed}}\,\,{\text{distance}} - {\text{slipped}}\,\,{\text{distance}}}}$$$$\eqalign{ & = {\frac{{x - z}}{{y - z}}} \times t \cr & = {\frac{{11 - 0.5}}{{1 - 0.5}}} \times 1 \cr & = 21\,\,{\text{minutes}} \cr} $$
Related Questions on Speed Time and Distance
A. 48 min.
B. 60 min.
C. 42 min.
D. 62 min.
E. 66 min.
A. 262.4 km
B. 260 km
C. 283.33 km
D. 275 km
E. None of these
A. 4 hours
B. 4 hours 30 min.
C. 4 hours 45 min.
D. 5 hours
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