Question
The speeds of two trains are in the ratio 7:9. If the
first train travels 315 km in 3 hours, how far will the second train travel in 5 hours?Solution
Let the speeds of two trains are 7x, 9x Speed of first train =315/3 = 105 km/h 7x = 105 x = 15 speed of second train = 9x = 135 km/h distance covered in 5 hours by second train = 135×5 = 675 km
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If  x = 19 , find x 5 - 20  x 4 + 20  x 3 - 20x 2 + 20x  - 20 = ?
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If x2a = y2b =z2c ≠ 0 and x2 = yz, then the value of (ab + bc + ca) /bc is :
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Given that x = 80, y = -35 and z = -45, Determine the value of [(x³ + y³ + z³)/10³]
22% of ‘x’ is equal to 66% of ‘y’, then find the value of x: y.
If, 4x + y = 10, and 2xy = 8, and 4x > y, then find the value of 64x³ – y³.
