Answer:
-13.37500
Step-by-step explanation:i dont know but there is the answer
Answer:
A can speak french
There are 10 students who can speak french, 4 girls and 6 boys
P(french) = speak french/ total
= 10/30
= 1/3
B is a boy
There are 16 boys
P (boy) = boys/total
= 16/30
8/15
C girl who can speak french
There are 4 girls who can speak french
P (girl who can speak french) = girl who can speak french/ total
=4/30
2/15
-8 3/8 = -8 15/40
-12 4/5 = -12 32/40 ,because you had to get a common denominator.
Since you are subtracting from a negative the negative turns into a positive.
-8 15/40 + 12 32/40 = 4 17/40
Answer:
F test
Step-by-step explanation:
Given that we want to study the average weight of children in the US. We collect a random sample of 345 first graders in three different US states
Since there are three samples representing three populations to check whether they have same average weight we have to use F test.
Two sample t test is wrong because here there are three samples.
Paired t test is done for the same item subject to two different tratments
Z test is done for comparing of a mean with population mean or proportion if the population standard deviation is known.
Hence here since the number of groups are more than two, only F test is best suited to determine whether there is a difference in the average student weight among the three states
This is a ratio problem. First, we need to add the number of students polled.
7 + 4 + 3 + 6 = 20
Next, look at how many out of 20 students selected Science.
3 out of 20.
Say it this way:
3 is to 20 as ? is to 400.
Express it this way:
3/20 = x/400
Cross multiply to eliminate the denominators.
3 x 400 = 20 x Now solve for x.
1200 = 20 x
x = 60
Check it!
Does 60/400 reduce to 3/20? Yes!
60 students are predicted to select science out of 400