Find the percentage of electrons were removed?

[blackbyron]

Homework Statement

A neutral object contains an equal number of positive and negative charges. A particular neutral object contains 7.2e26 electrons. If 9.5e6 electrons are removed, what percentage of the electrons where removed?

Homework Equations

coulomb = 6.24e18 electrons

elentary charge = 1.6 E -19 coulombs

The Attempt at a Solution

I'm having difficulties of solving the percentage of the electrons were removed,

I did this:

9.5e6 / 7.2e26 = 1.32e-20

But the answer says it's 1.32e-18, so I don't know how it got that answer.

Any help will be appreciated.

Thanks

 

[Mark44]

Homework Statement

A neutral object contains an equal number of positive and negative charges. A particular neutral object contains 7.2e26 electrons. If 9.5e6 electrons are removed, what percentage of the electrons where removed?

Homework Equations

coulomb = 6.24e18 electrons

elentary charge = 1.6 E -19 coulombs

The Attempt at a Solution

I'm having difficulties of solving the percentage of the electrons were removed,

I did this:

9.5e6 / 7.2e26 = 1.32e-20

But the answer says it's 1.32e-18, so I don't know how it got that answer.

Any help will be appreciated.

Thanks

To convert a number to a percentage, multiply by 100.

 

[blackbyron]

To convert a number to a percentage, multiply by 100.

Wow, I forgot about that. What am I thinking? haha thanks.