I'm so lost and need help with this problem!

Here's the question:

Aisha’s first summer job

requires her to travel downtown. She is

interested in finding out how most

people get to work each day, so she finds

the results of an online survey.

According to the survey below, what

percent of the workers walk to work?

Ok here is the info about how to reach the answer:

Drive Alone- 7,862,918

Carpool- 1,120,982

Take public Transit-144,959

Walk- 138,496

Other means- 149,641

Work At Home- 346,626

I have no clue how to find the answer. Please help.(Doh)