Take their combined sewing rate for 3 hrs.
So in 3 hrs, R can sew 32*3 and 7J can sew 32 buttons. Together they can sew 128 buttons in 3 hrs.
Solve for their combined average speed for sewing 1 button in minutes.
Multiply by 32 buttons = 45 mins
*If you qualify, the Free 360 Tutoring Program will be extended to you at no extra charge.
On top of the tutor you are getting, ManyTutors will provide unlimited free tutors to help you with any questions you may have for other subjects. Just snap a photo of your homework, post, and someone will provide the solution for free.
You will get a complimentary premium account on Ask ManyTutors that allows you to ask English, Chinese, Malay, Math, Science, Geography and History homework questions free of charge.
Under the 360 Program, the tutor will receive a different rate from what you are paying to ManyTutors.