To determine which scenario is true, we need to evaluate each option based on the total number of lessons and how many days it takes to complete them.
-
Option 1: Complete 312 lessons today and 412 lessons per day after that, completing 15 lessons in 7 more days.
- Total completed after 7 days: \( 312 + 412 \times 7 = 312 + 2884 = 3196\) (which is incorrect).
-
Option 2: Complete 3 1/2 lessons today and 4 1/2 lessons per day after that to complete 15 lessons in 7 more days.
- Total completed after 7 days: \( 3.5 + 4.5 \times 7 = 3.5 + 31.5 = 35.\) (which exceeds 15).
-
Option 3: Complete 4 1/2 lessons today and 3 1/2 lessons per day after that, completing the lessons in 3 more days.
- Total completed after 3 days: \( 4.5 + 3.5 \times 3 = 4.5 + 10.5 = 15 \). (this works).
-
Option 4: Complete 4 1/2 lessons today and 3 1/2 lessons per day after that, to complete the lessons in 3 more days.
- This is the same as option 3. The total is still 15 lessons.
-
Option 5: Complete 4 1/2 lessons today and 3 1/2 lessons per day to complete the lessons in 4 more days.
- Total computed total will show the same pattern as above, which will exceed.
-
Option 6: Complete 3 1/2 lessons today and 4 1/2 lessons per day to complete the lessons in 3 more days.
- Total for 3 days: \(3.5 + 4.5 \times 3 = 3.5 + 13.5 = 17\) (exceeds 15).
Analyzing the scenarios, options 3 and 4 are indeed valid real-world scenarios where the calculations add up to exactly 15 lessons in the specified time frame.
Hence, the correct answer is Option 3 or 4 (as they yield the same result).
1 answer