Question
A ship covers 96 km upstream and 144 km downstream in 8
hours and 6 hours, respectively. Find the time taken by the same ship to cover 180 km in still water.Solution
ATQ, Let speed of the ship in still water be ‘x’ km/h and speed of the stream be ‘y’ km/h Upstream speed of ship = (x – y) = (96/8) = 12 km/h --------- (I) Downstream speed of ship = (x + y) = (144/6) = 24 km/h ---------- (II) On adding equation (I) and equation (II), we have: 2x = 36 Or, x = 18 So, speed of the ship in still water = 18 km/h Therefore, time taken by the ship to cover 180 km in still water = (180/18) = 10 hours
5.45% of 1854 – 37.5% of 1096 = ? – 48% of 630
(12% of 1250 + 85% of 400) x 10 = ?2
(√121 + √196) × 7 =? × 5
1365 ÷ 15 + (? ÷ 5) = 62 × 3.5
(115 × 17 × 3)/(23 × 51) + ?3 = √169
60% of 250 + 14 × 10 - 210 = ?
(22.5 × 24) ÷ 40 + 51.50 = ? ÷ 5.25
60 = (? x 10 + 250)/5
65% of ? = 50 + 20 × 4
What will come in the place of question mark (?) in the given expression?
? = (27 × 13) – 26% of (412 – 92 )
