Respuesta :
Answer:
in about 0.92 hours or 55.2 minutes
Step-by-step explanation:
The time they take to paint the room:
Pragnesh and Qazi = 2 hours
Pragnesh and Ronghui = 3 hours
Qazi and Ronghui = 4 hours
Meaning, each hour (1) they'll paint:
Pragnesh and Qazi = [tex]\frac{1}{2th}[/tex] of the room
Pragnesh and Ronghui = [tex]\frac{1}{3th}[/tex] of the room
Qazi and Ronghui = [tex]\frac{1}{4th}[/tex] of the room
By summing all their work abilities we can determine how long it would take if all three students worked together to paint the fence, which is:
[tex]\frac{1}{2} + \frac{1}{3} + \frac{1}{4} = \frac{13}{12th}[/tex] of the room each hour. Therefore the whole (1) room would be painted in 1 ÷ [tex]\frac{13}{12}[/tex] = [tex]\frac{12}{13} hours[/tex] or 0.92 hours or 55.2 minutes (0.92 * 60).
