Answer:
20(E)
Step-by-step explanation:
Printing press R, S and T are working together at their respective constant rate.
They can do a job for 4 hours.
Let r, s and t be the time for printing press R, S and T to complete the job alone at their respective constant rate.
Rate of printing press R = 1/r
Rate of printing press S = 1/s
Rate of printing press T = 1/t
Rate = job / time
R + S + T = 4
1/r + 1/s + 1/t = 1/4
S + T = 5
1/s + 1/t = 1/5
Substitute 1/s + 1/t = 1/5 in the equation 1/r + 1/s + 1/t = 1/4
1/r + 1/5 = 1/4
1/r = 1/4 - 1/5
1/r = (5 - 4)/ 20
1/r = 1/20
r = 20 hours
It takes the printing press R 20 hours to complete the job alone
T hree
R idges
I n
A
N ice
G eometric
L ike
E ntity
Answer : Let Natalie's age be x. Let Fred's age be y. Add Fred's age to 3 times Natalie's age, the result is 65. Answer : Natalie is 13 years old and Fred is 26 years old.
Step-by-step explanation:
so sorry is wong
