There is a escalator going up to the second floor from the first floor.
If you go up to walk on the escalator, you will reach the second floor by 50 steps.
If you walk on the escalator doubled the speed of walking, you will reach the second floor by 60 steps.
How many steps are there in this escalator ?
Answer
75 steps
Solution
Assuming that the time of going up by 50 steps is set to 1.
The time concerning going up 60 steps with the same speed is 1 × 6/5 = 1.2.
Since when the speed is doubled, the time should be half of 1.2, it is 1.2 / 2 = 0.6.
Next, since the ratio of number of steps which escalator moved at the 1st time and the 2nd time is the same as the ratio of the time it moved, it is 1 : 0.6 = 5 : 3.
2 of the difference of 5 and 3 will be 60 steps - 50 steps = 10 steps.
If you go up to walk on the escalator, you will reach the second floor by 50 steps.
If you walk on the escalator doubled the speed of walking, you will reach the second floor by 60 steps.
How many steps are there in this escalator ?
Answer
75 steps
Solution
Assuming that the time of going up by 50 steps is set to 1.
The time concerning going up 60 steps with the same speed is 1 × 6/5 = 1.2.
Since when the speed is doubled, the time should be half of 1.2, it is 1.2 / 2 = 0.6.
Next, since the ratio of number of steps which escalator moved at the 1st time and the 2nd time is the same as the ratio of the time it moved, it is 1 : 0.6 = 5 : 3.
2 of the difference of 5 and 3 will be 60 steps - 50 steps = 10 steps.
Thus, it turns out that 5 is 10 step / 2 × 5 = 25 steps.
Therefore, the number of steps of this escalator is 50 steps + 25 steps = 75 steps.
Therefore, the number of steps of this escalator is 50 steps + 25 steps = 75 steps.
