Your Algebra 2 class has 20 students. 4 students are to be chosen at random for a project. A. How many groups of four are possible?

B. You are in the Algebra 2 class with 3 other friends. What is the probability that the four of you are chosen?

4845

.020639% (or 1/4845)

Step-by-step explanation:

For the first one we have to use combinations (because the order doesn't matter)

The formula is as follows:

for ACB

2.

for probabilty the odds of an outcome is just: number of times the requirement is satisfied/total number of possibliites

we know that there are 4845 possbile groups and only one in which we get all of our friends so it's just

1/4845= .020639%

10

step-by-step explanation:

7+3=10

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: