The first one is A and then the next one I believe should be 210 for both
Answer:
28 short race volunteers
76 long race volunteers
Step-by-step explanation:
Let :
Short races = a
Long races = b
LAST YEAR:
7a + 8b = 804 - - - - (1)
THIS YEAR:
11a + 5b = 688 - - - (2)
Multiply (1) by 5 and (2) by 8
35a + 40b = 4020
88a + 40b = 5504
Subtract
-53a = - 1484
a = 1484 / 53
a = 28
Put a = 28 in equation (1)
7(28) + 8b = 804
196 + 8b = 804
8b = 804 - 196
8b = 608
b = 76
28 short race volunteers
76 long race volunteers
Answer:
Let X the random variable of interest "Number of correct anwers on the tet", on this case we now that:
And the expected value is given by:

Step-by-step explanation:
Previous concepts
A Bernoulli trial is "a random experiment with exactly two possible outcomes, "success" and "failure", in which the probability of success is the same every time the experiment is conducted". And this experiment is a particular case of the binomial experiment.
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
Solution to the problem
Let X the random variable of interest "Number of correct anwers on the tet", on this case we now that:
And the expected value is given by:

To solve this problem, you should find the rate ---> cost per yogurt (cost/yogurt)
$6.50/10 yogurts = $0.65/yogurt
It costs $0.65 per yogurt, so you can multiply 9 by $0.65 to find the total cost of 9 yogurt.
9(0.65) = $5.85
6.842 or higher. When you line up the decimals, you see 6.842 has a 2 and 6.841 has a 1. 2 is greater than 1, more greater numbers are 6.843, 6.844, 6.845, etc.