Question
A is cycling at an average speed of 24 km/hr such that
he can reach a certain point at 12 noon. If he cycles at 36 km/hr, then he will reach the destination at 10 a.m. At what speed he should cycle to reach the destination at 11 a.m.Solution
Let the distance to be travelled be ‘x’ km Time taken when speed is 24 km/hr = (x/24) hours Time taken when speed is 36 km/hr = (x/36) hours According to the question, (x/24) – (x/36) = 2 Or, 3x – 2x = 2 × 72 Or, x = 144 km Time taken to travel 144 km with speed of 24 km/hr = 144/24 = 6 hours Therefore, he started at 12 – 6 = 6 a.m. Therefore, required speed to reach the destination at 11 a.m. or 4 hours = 144/5 = 28.8 km/hr
What will come in place of the question mark (?) in the following series?
92, 153, 220, ?, 364, 443
124, 147, 176, 207, 244, ?
Find the missing number, in the given number series.
25, 30, 40, 57, ?, 120
What value should come in the place of (?) in the following number series?
5670, 1620, 540, 216, 108, ?
600 Â Â Â 60Â Â Â 12Â Â Â ? Â Â Â Â 1.44Â Â Â Â 0.72
32   33    29   38    ?      47    11
...18, 37, 60, ?, 120, 157
117, 117, 121, 129, 141, ?
11   6   7   12   26    ?    205.5
827, 820, 806, 785, 757, ?
