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Question
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Split the fraction on the left
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Take away h/5 from both sides
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Change the denominator to be the same
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Put it into single fraction
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Rearrange (This step may not be necessary)
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You find a common denominator (the bottom one) and then add the numerator (the top) but you don't add the denominator, you just make it the same
If the turn out of an event is to take place or not to take place only then, the sum of the probability of it taking place and not taking place is 1. If we represent the probability of it taking place by x then, the probability of it not taking place is equal to 1 - x.