I'm going to have to go with choice "c". 10x - 1 with the remainder of 5
Answer: 52.94
Step-by-step explanation:
Length of train A = 480m
Tunnel length = 1320m
Time taken to cross tunnel = 2 mins = 120sec
Length of train B = 420m
Train B is slower than train A
Difference between their speed = 18km/hr
18km/hr = (18×1000)/3600 = 5m/s
Speed of train A :
Speed = distance / time
Speed = 1320 / 120 = 11m/s
Therefore, speed of train B :
(11 - 5)m/s = 6m/s
Relative speed of the two trains is therefore;
(Speed of A + speed of B)
Note : they are moving in opposite direction
( 11 + 6)m/s = 17m/s
Therefore time taken to cross each other :
(Sum of the length of both trains / relative speed of the trains)
Time taken = (480m + 420m) / (17m/s)
Time taken = 900m / 17m/s
Time taken = 52.94s
Part A. 615.44
Part B. 78.5
Answer:
Using the table
Maria does 1/4 of the job in 1 hour since it takes her 4 hours to complete the job , she works x hours and completes x/4 of the task
Josie does 1/2 of the job in 1 hour since it takes her 2 hours to complete the job , she works x hours and completes x/2
x/4 + x/2 = 1 completed task
Multiply by 4
x/4 *4 + x/2*4 = 1*4
x+2x =4
3x=4
x = 4/3
x = 1 1/3 hours
