Take how much money she needs, which is $175. Subtract $10 from that. You get $165. Now divide that by $5. $165 divided by $5 is 33. That's 33 months. BUT, we also have to include the first month (because that month is saving money too, $10). So that month (1) plus the others (33) equals 34 months.
If it's 40 minutes for just 5 papers, we need to figure how many minutes it would take to grade just 1. So you have to divide 40 by 5 which is 8. Then 8 time 30 which is 240.
