### 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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## Comments

Geez, ok. I'll take your word for it.

very cute puzzle. Interesting how the answer doesn't depend on what the two numbers are at all.

Good one!

BTW....

The two numbers are 4 + SQRT(2) and 4 - SQRT(2) .

Good one!

BTW....

The two numbers are 4 + SQRT(2) and 4 - SQRT(2) .

If I were REALLY clever, I would not have needed to be told how I could solve this if I were clever!

Very clever teaser! Easy enough to do, but interesting nonetheless.

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