Brain Teasers
Sum of Reciprocals
If the sum of two numbers is 8, and their product is 14, what is the sum of their reciprocals?
If you're clever, you can solve this without having to figure out what each of the numbers is.
If you're clever, you can solve this without having to figure out what each of the numbers is.
Answer
4/7Note: 1/a + 1/b = (a+b)/ab
and since a+b=8 and ab = 14
then 1/a + 1/b = 8/14 = 4/7
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