Answer:
It takes 70 minutes for 9 team members (painting 60 sq ft per minute) to paint a 4200 sq ft wall.
Step-by-step explanation:
According to the situation the calculation is shown below:-
= ![\frac{4800}{20}](https://tex.z-dn.net/?f=%5Cfrac%7B4800%7D%7B20%7D)
= 240 sq ft each member of the team in 36 minutes
= ![\frac{240}{36}](https://tex.z-dn.net/?f=%5Cfrac%7B240%7D%7B36%7D)
= 6.67 sq ft each member of the team within 1 minute
![= 6.67\times 9](https://tex.z-dn.net/?f=%3D%206.67%5Ctimes%209)
= 60 sq ft for every 9 team members in one minute
= ![\frac{4200}{60}](https://tex.z-dn.net/?f=%5Cfrac%7B4200%7D%7B60%7D)
= 70 minutes (or 1 hour and 10 minutes)
Hence, the 70 minutes is taken for 9 team members