Suppose you stacked pennies after 22 days. How high would the stack rise, in kilometers?

Guest Mar 13, 2017

#1**0 **

Suppose you stacked pennies after 22 days. How high would the stack rise, in kilometers?

I assume you mean you stack 1 penny the first day, add 2 the second day, add 4 the third day. etc

\(1+2+4+ .... 2^{k-1}.........+ 2^{22-1}\\ \boxed{S_n=\frac{a(r^n-1)}{r-1}}\\ S_n=\frac{1(2^{22}-1)}{2-1}\\ S_n=2^{22}-1\\\)

I found this on the web i assume it means a penny is 1.52mm thick.

The United States one- cent coin oft called penny , is a unit of currency equaling ... The coin is 0.75 inches (19.5 mm) in diameter and 0.0598 inches (1:52 mm) in thickness .

((2^22-1)*1.52)/(1000*1000) = 6.37534056

So that is approximately 6.4 kilometres

Melody
Mar 13, 2017