The bell rings for school at 8:30 a.m. Elia must be there 15 minute before the bell. The trip to school takes 35 min. When should Elisa leave for school.

You could simply count on your fingers -- or you can subtract from the equivalent of 8:30.

7:90 - 50 = ?

8:30-15=8:15

8:15-35=7:40

7:40

To determine when Elia should leave for school, we need to calculate the total time it would take her to get there.

First, we consider the time she needs to be at school before the bell rings. Elia must be there 15 minutes before the bell, so we add 15 minutes to the time the bell rings:

8:30 a.m. + 15 minutes = 8:45 a.m.

Next, we account for the time it takes for Elia to travel to school. The trip to school takes 35 minutes.

To find the total time, we add the travel time to the time she needs to be at school:

8:45 a.m. + 35 minutes = 9:20 a.m.

Therefore, Elia should leave for school at 9:20 a.m.