Question
A man can row the boat x km downstream and the same
distance upstream in 12 hours. Also, he can row the boat 5x km downstream in 10 hours. At what time, he can row the x km distance upstream?Solution
Let the downstream speed of the boat be ‘a’km/h According to the question, (5x/a) = 10 Or (x/a) = (10/5) Or (x/a) = 2 = time taken to travel ‘x’ km downstream Let the upstream speed of the boat be ‘b.’ km/h Also, (x/a) + (x/b) = 12 2 + x/b = 12 x / b = 10 hours
What will come in the place of question mark (?) in the given expression?
(144 × 16 ÷ 12) × 6 = ?
35% of 840 + 162 = ? – 25% × 300
10³ = (? – 6) × 320 ÷ 8
((12+12+12+12)÷4)/((8+8+8+8+8+8)÷16) = ?
√10404 + √9604 - ∛1728 - ∛42875 = ?
721 +21 x 9 - 118 = ? + 82
2 X 25 + (30% of 80) ÷ (10% of 120) = ?
3/7 of 504 ÷ 12 + 17 = √?
What should come in place of (?) question mark in the given expression.
(2⁵ × 3⁴) ÷ (6³) = ?