SOLUTION: A grandmother, her daughter and her granddaughter can say this year that the sum of their ages is 100. In which year was the granddaughter born, if each age is a power of 2?

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Question 865074: A grandmother, her daughter and her granddaughter can say this year that the sum of their ages is 100. In which year was the granddaughter born, if each age is a power of 2?
Answer by solver91311(24713)   (Show Source): You can put this solution on YOUR website!


The only 3 powers of 2 that sum to exactly 100 are 64, 32, and 4. But specifying the birth year becomes problematic since you don't know the month and day for each of the three people. For example, Grandma could possibly have turned 64 sometime after today's month and day in 2013, meaning that she would have been born in 1949, or she could have been born earlier in the year, meaning that she was born in 1950. Same thing with the other two people, so there are actually 8 different answers to this question, all of which are possibly correct. I'll leave it to you to figure out all of the possibilities.

John

My calculator said it, I believe it, that settles it
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