Question
The speed of a boat in still water is 28 km/hr. If the
boat covers 140 km in upstream in 7 hours, then find the time taken by the boat to travel 144 km in downstream.Solution
Let the speed of the boat in still water and the speed of the current be ‘x’ km/hr and ‘y’ km/hr, respectively Upstream speed of the boat = (x – y) = 140/7 = 20 km/hr Or, 28 – y = 20 Or, y = 28 – 20 = 8 km/hr Therefore, downstream speed of the boat = 28 + 8 = 36 km/hr Required time taken = 144/36 = 4 hours
? = 650.24 + 1124.97 – 14.992
124% of 620.99 + 11.65% of 1279.23 = ?
What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)...
6527.83 - 4891.21 + 7423.46 + ? = 14520.34
20% of 80 × 26% of 65 = ?
185.92 ÷ 5.98 - (4.002)2 + 114.03 of 5.03 ÷ 18.99 of 6.04 = 5.01 of 2.99 + ? ÷ 12.02
What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)...
`sqrt623.798` × 24.034 +`sqrt403.898` × 17.907 =?
600.11 ÷ 14.98 x 5.14 – 171.9 = √?
