Melissa returned home from mowing lawns at 4:15 PM. It took 1 and ¾ hours of an hour to mow the first lawn. The second and third lawns she mowed each took 1 and ⅕ hours. She took only a 45-minute break. When did Melissa begin mowing the first lawn?
subtract 1:45 + 2(1:12) + 0:45 from 4:15 pm
To determine when Melissa began mowing the first lawn, we'll need to add up the amount of time she spent mowing the three lawns and the time she spent on her break.
Let's break down the given information:
- Melissa returned home from mowing lawns at 4:15 PM.
- It took 1 and ¾ hours to mow the first lawn.
- The second and third lawns each took 1 and ⅕ hours.
- She took a 45-minute break.
To solve this, we'll start with the time Melissa returned home and deduct the total time she spent on mowing and her break.
Step 1: Convert all the given times into minutes.
- 1 and ¾ hours = 1 × 60 minutes + ¾ × 60 minutes = 60 + 45 = 105 minutes
- 1 and ⅕ hours = 1 × 60 minutes + ⅕ × 60 minutes = 60 + 12 = 72 minutes
- 45 minutes = 45 minutes
Step 2: Calculate the total time spent on mowing the lawns.
- First lawn: 105 minutes
- Second lawn: 72 minutes
- Third lawn: 72 minutes
Total mowing time = 105 minutes + 72 minutes + 72 minutes = 249 minutes.
Step 3: Add the total mowing time to the time Melissa returned home.
- 4:15 PM + 249 minutes = 4:15 PM + 4 hours and 9 minutes = 8:24 PM
Therefore, Melissa began mowing the first lawn at 8:24 PM.