Answer:the plane in still air is 904 km/h
the rate of the wind is 104 km/h
Step-by-step explanation:
Let x represent the rate or speed of the plane in still air.
Let y represent the rate or speed of the wind.
Flying against the wind, an airplane travels 4000 kilometers in 5 hours. This means that the total speed of the airplane would be (x - y) km/h
Distance = speed × time
Therefore
4000 = 5(x - y)
4000 = 5x - 5y - - - - - - - - -1
Flying with the wind, the same plane travels 5040 kilometers in 4 hours. This means that the total speed of the airplane would be (x + y) km/h. Therefore,
5040 = 4(x + y)
5040 = 4x + 4y - - - - - - - - - 2
Multiplying equation 1 by 4 and equation 2 by 5, it becomes
16000 = 20x - 20y
20160 = 20x + 20y
Subtracting, it becomes
- 4160 = - 40y
y = - 4160/-40
y = 104
Substituting y = 104 into equation 1, it becomes
4000 = 5x - 5 × 104
4000 = 5x - 520
5x = 4000 + 520
5x = 4520
x = 4520/5 = 904
Todd needs to save $90.75 per month to reach his goal
Answer:
b. MLR.3 - No perfect collinearity assumption
Step-by-step explanation:
There is an assumption that nothing in the error term should correlate with the explanatory variable (x) of interest and outcome variable of (y). It does not allow any linear relation between two or more variables. If there is a relation between the variable it the the violation of this assumption.
Answer: x =3
Step-by-step explanation:
2× 3 = 6
length= 5 inches
width= 2×3= 6 inches
2(l+w) = 2(5+6)
2(11)
2×11= 22
hope this helps:-)
