Answers

2015-03-09T23:02:25+05:30
5 stairs per second and 2 stairs down the next second
so she climbs 5-2 stairs every 2 seconds
to climb 60 stairs
3 stairs 2 sec
60 stairs = ?
60/3 × 2 = 40 seconds
she would take 40 seconds to climb 60 stairs

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2015-03-10T12:02:29+05:30
She climbs stairs every second=5. She climbs down over next second=2. She climbs stair in 2 second =5-2=3 stairs She will climb 60 stair in second = 60/3×2=40 sec. So , she climbs 60 stairs in 40 seconds.
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