Answer:
The time it will take them to meet each other is 1 hour and 30 minutes.
Explanation:
Given:
Sally and molly are 12 miles away from each other.
Sally runs 5 mph towards Molly, and Molly walks 3 mph towards Sally.
Now, to find the time it will take them to meet each other.
Let the time be
![x.](https://img.qammunity.org/2021/formulas/mathematics/middle-school/mmi228653dkvma4dszwy75q6dvkduzr4zg.png)
Total distance = 12 miles.
Now, find the distance by putting formula:
Distance = speed × time.
Distance Sally runs towards Molly (D1) =
![5* x=5x.](https://img.qammunity.org/2021/formulas/mathematics/middle-school/n01vnw932z4juqtxczvv5o2sjyw8ckk8zl.png)
Distance Molly walks towards Sally (D2) =
![3* x=3x.](https://img.qammunity.org/2021/formulas/mathematics/middle-school/c07bsy3p6988yerina47fold7duy5g6pmc.png)
Now, to get the time:
Total distance = D1 + D2.
![12=5x+3x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/7su38a4fxcqmduotc3wxe2dxqhw7tirk7g.png)
![12=8x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/egjp4ts3y6id9tu0txd3q85nnyhdxo7ojd.png)
Dividing both sides by 8 we get:
![(3)/(2) =x](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ft5xswv6bxwxa1i9eodd0no1i4jpxyc4pk.png)
![x=(3)/(2)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/9lptuiq4bcqodvdlmlur0psiy5koj6km37.png)
![x=1(1)/(2)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/jsc59q1ruug2ztgck05nnoajvxdhh2y5wj.png)
The time = 1 and 1/2 hour.
That is 1hour and 30 minutes.
Therefore, the time it will take them to meet each other is 1 hour and 30 minutes.