Question
Naveen walking at a speed of 15 km/h reaches his office
20 minutes late. Next time he increases his speed by 5 km/h, but he finds he is still late by 5 minutes. What is the distance of his office from his house?Solution
Let the distance be D. D/15 = T + 20/60 ……. (i) D/20 = T + 5/60 ……. (i) Form (i) and (ii) we get, D x 1/60 = 15/60 D = 15 km. Alternate method: Distance = Time gap× product of speeds/ gap of speed = 15 min×15×20/(20-15) = 15/60 hrs ×15×20/5 = 15 Km
[(145)² ÷ 25 × 52] ÷ ? = 29 × 13
What will come in place of (?) question mark in the given number series.
13, 15, 18, 23, 30, ?
123, 122, 114, 87, ?, -102
380, ?, 360, 324, 260, 160
418, 406, 430, 382, 478, ?, 670
728, 737, ?, 778, 814, 863
250 25 5 ? 0.6 0.3
- What will come in place of (?) in the given number series.
1, 2, 6, 21, 88, ? 10, 10, 15, 30, 75, ?
58, 63, 78, ?, 138, 183