Respuesta :
Answer:
The sidewalk moves at 0.5 ft/sec
Josie's speed walking on a non-moving ground is 3.5ft/sec
Step-by-step explanation:
Let x represent the speed of the side walk and y represent her walking speed
It takes Jason's 8-year-old daughter Josie 44 sec to travel 176 ft walking with the sidewalk
Distance = speed × time
176 = (x+y)×44
44x+44y = 176
x+y = 4 .......1
It takes her 7 sec to walk 21 ft against the moving sidewalk in the opposite direction).
21 = (y-x)7
7y - 7x = 21
y - x = 3 ......2
Add equation 1 to 2
2y = 7
y = 3.5 ft/sec
From equation 1
x + y = 4
x = 4 - 3.5 = 0.5
x = 0.5 ft/sec
The sidewalk moves at 0.5 ft/sec
Josie's speed walking on a non-moving ground is 3.5ft/sec
Answer: Josie's speed walking on a non-moving ground is 3.5 ft/sec
The side walk moves at 0.5 Ft/sec
Step-by-step explanation:
Let x represent Josie's speed walking on a non-moving ground.
Let y represent the speed of the sidewalk.
It takes Jason's 8-year-old daughter Josie 44 sec to travel 176 ft walking with the sidewalk. It means that the total speed at which she moved is
(x + y) ft/sec
Distance = speed × time
Therefore,
176 = 44(x + y)
Dividing both sides by 44, it becomes
4 = x + y- - - - - - - - - - - - - -1
It takes her 7 sec to walk 21 ft against the moving sidewalk in the opposite direction). It means that the total speed at which she moved is (x - y) ft/sec
Therefore,
21 = 7(x - y)
Dividing both sides by 7, it becomes
3 = x - y- - - - - - - - - - - - - -2
Adding equation 1 and 2, it becomes
7 = 2x
x = 7/2 = 3.5 ft/sec
Substituting x = 3.5 into equation 2, it becomes
3 = 3.5 - y
y = 3.5 - 3 = 0.5 ft/sec
