Answer:
10
Step-by-step explanation:

The normal distribution curve for the problem is shown below
We need to standardise the value X=405.5 by using the formula


We now need to find the probability of z=0.32 by reading the z-table
Note that z-table would give the reading to the left of z-score, so if your aim is to work out the area to the right of a z-score, then you'd need to do:

from the z-table, the reading

gives 0.6255
hence,

The probability that the mean weight for a sample of 40 trout exceeds 405.5 gram is 0.3475 = 34.75%
Answer:
-9
Step-by-step explanation:
Parentheses first:16-35+4 = -35+16+4 = -35+20 = -15
3(-15) = -45/5
-45 divided by 5 = -9
Step-by-step explanation:
The volume of a pyramid or cone is:
V = ⅓ Ah
where A is the area of the base and h is the height.
The pyramid has a square base, so:
A = s²
A = (7 cm)²
A = 49 cm²
The height is 14 cm, so the volume is:
V = ⅓ (49 cm²) (14 cm)
V = 686/3 cm³
V ≈ 228.67 cm³
So there are 52 horses
12 of them are white
how many are black?
52 - 12 = 40
there are 40 black horses
12 white horses to 40 black horses
12:40
12/40
Hope this helps :)