Posted by Monica on .
A proton has a size of 0.000000000123 and an electron has a size of 1.4x10^8. How many times smaller is an electron than a proton?
Show your work.

Math 
Steve,
proton = 1.23*10^11
elec = 1.4*10^8
elec/prot = 1.4/1.23 * 10^3 = 1138 
Math 
Monica,
I thought the proton would have to be in the numerator and the electron would be in the denominator for you to divide?

Math 
Steve,
they ask the ratio of electron to proton. That is, how many times as big is the electron?
The proton is 1/1138 as big as the electron, meaning it is 1138 times as small.