A number was increased by 40% and thereafter decreased by 40%. The net change in the number in percentage is [#1689]

16% decrease = 40-40-$\frac{40*40}{100}$% = -$\frac{1600}{100}$% = -16%

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16% decrease = 40-40-$\frac{40*40}{100}$% = -$\frac{1600}{100}$% = -16%

An integer is a whole number, either positive, negative, or zero, without a decimal or fractional part, such as 5, -3, or 0.

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An integer is a whole number, either positive, negative, or zero, without a decimal or fractional part, such as 5, -3, or 0.

Net change (-40 + 20 + $\frac{(-40)*20}{100}$)% = (-20 + $\frac{-800}{100}$)% = (-20 - 8)% = -28% = 28%

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Net change (-40 + 20 + $\frac{(-40)*20}{100}$)% = (-20 + $\frac{-800}{100}$)% = (-20 - 8)% = -28% = 28%

=> 2x * 3x = 96 => 6x² = 96 => x² = 96/6 => x² = 16 => x = 4 2x + 3x = 5x = 5 * 4 = 20

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=> 2x * 3x = 96 => 6x² = 96 => x² = 96/6 => x² = 16 => x = 4 2x + 3x = 5x = 5 * 4 = 20

The formula for the sum of the first n terms of an arithmetic progression is $S_n\mathit{ }\mathit{=}\mathit{ }\frac{n}{2}(a+an)$ $\frac{30}{2}(12+12*30)$ = 15*(12+360) = 15 * 372 = 5580

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The formula for the sum of the first n terms of an arithmetic progression is $S_n\mathit{ }\mathit{=}\mathit{ }\frac{n}{2}(a+an)$ $\frac{30}{2}(12+12*30)$ = 15*(12+360) = 15 * 372 = 5580

A starts journey before B at a speed of 1 m/s. Hence A will be ahead of B (10*60)s * 1m/s = 600m Let A covers a distance of X after starting of B, Then X + 600m = 2X => 2X - X = 600m => X = 600m Hence B will cover a distance of 2X = 2 * 600m = 1200m = 1.2 km

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A starts journey before B at a speed of 1 m/s. Hence A will be ahead of B (10*60)s * 1m/s = 600m Let A covers a distance of X after starting of B, Then X + 600m = 2X => 2X - X = 600m => X = 600m Hence B will cover a distance of 2X = 2 * 600m = 1200m = 1.2 km

17 which is a Prime number.

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17 which is a Prime number.

The son becomes 15 years old after 3 years. Hence son's present age = 15 years - 3 years = 12 years Man is four times as old as his son. Hence Man's present age = 12 years * 4 = 48 years Man is 3 years older than his wife. Hence present age of his wife = 48 years - 3 years = 45 years.

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The son becomes 15 years old after 3 years. Hence son's present age = 15 years - 3 years = 12 years Man is four times as old as his son. Hence Man's present age = 12 years * 4 = 48 years Man is 3 years older than his wife. Hence present age of his wife = 48 years - 3 years = 45 years.

27

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27

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.

20% of a is b Hence b = 20% of a = 20a/100 b% of 20 = 20% of b = (20/100) * 20a/100 = (20*20*a)/(100*100) = 4a/100 = (4/100) * a = 4% of a

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20% of a is b Hence b = 20% of a = 20a/100 b% of 20 = 20% of b = (20/100) * 20a/100 = (20*20*a)/(100*100) = 4a/100 = (4/100) * a = 4% of a