Working simultaneously and independently at an identical constant rate, 20 machines of a certain ...
Working simultaneously and independently at an identical constant rate, 20 machines of a certain type can produce a total of x units of product P in 4 days. How many of these machines, working simultaneously and independently at this constant rate, can produce a total of 3x units of product P in 8 days?
Answer/Solution
30
Steps/Work
The rate of 20 machines is rate=job/time=x/4 units per day --> the rate of 1 machine 1/20*(x/4)=x/80 units per day;
Now, again as {time}*{combined rate}={job done}
then 8*(m*x/80)=3x --> m=30.
Answer: A.
Now, again as {time}*{combined rate}={job done}
then 8*(m*x/80)=3x --> m=30.
Answer: A.