Answer:
The answer is 8/5 or 8 out of 5.
Step-by-step explanation:
In order to solve this you need to first add the number of envelopes together to get the sum of how many envelopes there are, 1 + 3 + 2 + 2 = 8. Next you add the amount of blue and green envelopes together 3 + 2 = 5. The total number of envelopes is 8, and 5 out of the 8 are green or blue, therefore you will have a 8 out of 5 chance of picking one of those colors.
Answer:
x=20
Step-by-step explanation:
x - 5 = 15
x +5 = +5
x = 20
Answer:
4
Step-by-step explanation:
If each weight is the same than we can simple multiply the weight of one by the number of weights there are

Answer:
a) For this case we can use the definition of weighted average given by:

And if we replace the values given we have:

b) 
c) 
Step-by-step explanation:
Assuming the following question: "One sample has a mean of M=8 and a second sample has a mean of M=16 . The two samples are combined into a single set of scores.
a) What is the mean for the combined set if both of the original samples have n=4 scores
"
For this case we can use the definition of weighted average given by:

And if we replace the values given we have:

b) what is the mean for the combined set if the first sample has n=3 and the second sample has n=5
Using the definition we have:

c) what is the mean for the combined set if the first sample has n=5 and the second sample has n=3
Using the definition we have:

Answer:
13.2 minutes or 13 minutes 12 seconds.
Step-by-step explanation:
1. Count how much water drains the first pump every minute. Let the volume of pool be D. Every minute first pump drains D/11 water.
2. Working together(6 minutes) First pump drains 6D/11 water, hence the second pump drains 5D/11 water.
3.Count how much water drains second pump per minute -> (5D/11)/6= 5D/66
4. It takes the second pump 66 minutes to drain pool 5 times, thus it takes 13.2(66/5) minutes to drain the pool, which is 13 minutes 12 seconds.