An aunt gives her niece $1 on her first birthday, $2 on her second birthday, $4 on her third birthday and so on, doubling the amount each year. On which birthday was the niece given more than $1000 for the first time

Question

Alessandro Castaneda

Mathematics

1 February, 13:46

An aunt gives her niece $1 on her first birthday, $2 on her second birthday, $4 on her third birthday and so on, doubling the amount each year. On which birthday was the niece given more than $1000 for the first time

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Answers (2)

Know the Answer?

Yadira Moses · Answer 1

Just compute the amount by doubling and stop at the amount more than a $1000.

Amount: 1,2,4,8,16,32,64,128,256, 512, 1024.

Year: 1,2,3,4, 5, 6, 7, 8, 9,.10, 11.

On her eleventh brithday her Aunty would give her $1024.

Cheers.

Tanner Nixon · Answer 2

On the day she turned 11 years old, the niece was given $1,024.

But wait! It gets better!

If the aunt was still alive and well, and in a generous mood, on the day

her niece turned 21 years old, then her gift on that day was $1,048,576.

And the sum of all the gifts up until that birthday was $2,097,151.