Arithmetic

Question

80 machines can produce 4800 identical pens in 5 hours, At this rate how many pens would one machine produce in one hour? and how many pens would 25 machines produce in 7 hours?

Answer 1

R=(4800 pens)/(80mach•5hrs)

 

R=12 pens/(mach-hr)

 

12 pens are made by one machine in one hour. 

 

P=(12 pens/(mach-hr))•

        (25 mach)(7 hrs)

 

note the units of machine and hours cancel

 

P=2100 pens

 

2100 pens are made by 25 machines in 7 hours