I got 1 but the question is really not detail sooo
Answer:
The ratio is the same
Step-by-step explanation:
Bianca- 20:14
= 10:7
Logan- 10:7
The ratio is the same
Answer:Four years ago, Alex was twice as old as Jake. Four years from now, Jake will be 3/4 of Alex's age. How old is Alex? - Answer: 12.
Step-by-step explanation:
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