Answer:
The ratio between won and lost is 
Step-by-step explanation:
<u><em>The question in English is</em></u>
A table tennis team won 21 games and lost 12 games, what is the ratio between won and lost?
Let
x ------> the number of games won
y -----> the number of games lost
we have


we know that
To find the ratio divide the number of games won by the number of games lost
so

substitute the values

Simplify

Answer:
I'm confused too I'm sorry
Answer:
a) The mean is 
b) The standard deviation is 
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
The probability a student selected at random takes at least 55.50 minutes to complete the examination equals 0.6915.
This means that when X = 55.5, Z has a pvalue of 1 - 0.6915 = 0.3085. This means that when 
So




The probability a student selected at random takes no more than 71.52 minutes to complete the examination equals 0.8997.
This means that when X = 71.52, Z has a pvalue of 0.8997. This means that when 
So




Since we also have that 





Question
The mean is 
The standard deviation is 
48π cm^3
Step-by-step explanation:
The formula for the volume of a cone is...

We can plug everything we know from the photo into the equation, but note that the picture gives us the diameter, which is 8, instead of the radius. The radius is half of the diameter, so the radius will be 4. Also we will be leaving pi as it is, instead of changing it to 3.14.


V = 48π
The paper cone can hold <u><em>48π cubic centimeters</em></u> of water.