Two trains of 200 m and 100 m long are running parallel at the rate of 20 m/sec. and 22 m/sec. respectively. How much time will they take to cross each other, if the trains are running along the same direction? [#1132]

The difference of speed = 22m/s - 20m/s = 2m/s As the train with speed 22m/s will cross the other, hence this train have to go the smallest length of the trains distance ahead of the other to cross completely. Hence This train will be ahead of 100m with a speed of 2m/s. Hence The time to cross each other will take = 100m / (2m/s) = 50 sec

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The difference of speed = 22m/s - 20m/s = 2m/s As the train with speed 22m/s will cross the other, hence this train have to go the smallest length of the trains distance ahead of the other to cross completely. Hence This train will be ahead of 100m with a speed of 2m/s. Hence The time to cross each other will take = 100m / (2m/s) = 50 sec

5² + X² = 13² => 25 + X² = 169 => X² = 196 - 25 => X² = 144 => X = 12

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5² + X² = 13² => 25 + X² = 169 => X² = 196 - 25 => X² = 144 => X = 12

7 => x * 2x = 98 => x² = $\frac{98}{2}$ => x² = 49 => x = 7

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7 => x * 2x = 98 => x² = $\frac{98}{2}$ => x² = 49 => x = 7

100 - 98 = 2

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100 - 98 = 2

6*4 = 24 8*3 = 24 12*2 = 24

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6*4 = 24 8*3 = 24 12*2 = 24

An obtuse angle is an angle greater than 90 degrees but less than 180 degrees, like the angle formed by two walls that meet at a corner.

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An obtuse angle is an angle greater than 90 degrees but less than 180 degrees, like the angle formed by two walls that meet at a corner.

1+3+5+7+9+11+13 = 49

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1+3+5+7+9+11+13 = 49

X * (X-12) = 40 * 4 X = 20 X + (X-12) = 20 + 20 - 12 = 28

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X * (X-12) = 40 * 4 X = 20 X + (X-12) = 20 + 20 - 12 = 28

2 * $\frac{22}{7}$ * 7 = 2 * 22 = 44

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2 * $\frac{22}{7}$ * 7 = 2 * 22 = 44

Area = πr² π1² : π3² = π1 : π9 = 1:9

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Area = πr² π1² : π3² = π1 : π9 = 1:9