MATHS

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how much money would you have after 20 weeks if you were given 5c the first week, 10c the second, 20c the third, 40c the fourth, and so on?

• MATHS -

looks like a geometric series

5 + 10 + 20 + 40 + ... for 20 terms

a = 5 , r = 2
Sum(2) = 5(2^20 - 1)/(2-1) = 5242875 c

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