Answer:
52 feet apart
Step-by-step explanation:
20 + 32 = 52
Answer:

--- Variance
Step-by-step explanation:
Given

Solving (a): Calculate the mean.
The given data is a grouped data. So, first we calculate the class midpoint (x)
For 51 - 58.

For 59 - 66

For 67 - 74

For 75 - 82

For 83 - 90

So, the table becomes:

The mean is then calculated as:



-- approximated
Solving (b): The sample variance:
This is calculated as:

So, we have:


-- approximated
Answer:
The speed of the boat in still water is 18 mph.
The speed of the current is 2 mph
Step-by-step explanation:
Let x represent the speed of the boat in still water.
Let y represent the speed of the current.
When the boat goes against the current, the speed is 16 mph. Assuming it traveled against the current while going upstream, its total speed would be (x - y) mph. It means that
x - y = 16 (equation 1)
Going downstream, the boat averages 20 mph. Assuming it traveled with the current, its total speed would be (x + y) mph. It means that
x + y = 20 (equation 2)
Adding both equations, it becomes
2x = 36
x = 36/2
x = 18 mph
Substituting x = 18 into equation 1, it becomes
18 - y = 16
y = 18 - 16
y = 2 mph
Answer:
The number is -9.
Step-by-step explanation:
If we let the number be x we have the equation 6x + 7 = -47.
6x + 7 - 7 = -47 - 7
6x = -54
x = 054/6
x = -9.
The answer to your question is D , it is 2/3 simple math even easier if you use a calcul