7-3=4
9-2=7
4x7=28
Use PEMDAS for order of operations, it will save your life
Parenthesis Exponents Multiply Divide Add Subtract
Multiply and Divide and Add and Subtract can be switched around with each other, but multiply and divide always happens before add and subtract. The reason you add first here is because it is in the parenthesis.
Answer:
240
Step-by-step explanation:
-8(10×-3)
(10×3)=30
30×-8=240
Answer:
0.1 = 10% probability that the class length is between 51.5 and 51.7 min, that is, P(51.5 < X < 51.7) = 0.1.
Step-by-step explanation:
A distribution is called uniform if each outcome has the same probability of happening.
The uniform distributon has two bounds, a and b, and the probability of finding a value between c and d is given by:

The lengths of a professor's classes has a continuous uniform distribution between 50.0 min and 52.0 min.
This means that 
If one such class is randomly selected, find the probability that the class length is between 51.5 and 51.7 min.

0.1 = 10% probability that the class length is between 51.5 and 51.7 min, that is, P(51.5 < X < 51.7) = 0.1.
27 divided by 15 is 1.8, so that should be the correct answer.
The amount of balls in a given layer can be found by squaring the layer it is in
4 layers
top layer (1st) is 1
2nd is 4
3rd layer is 9
4th is 16
add them up
1+4+9+16=30
30 in that pyramid