Which number is irrational?
A. 25
B. 0.636363...
C. 0.45
D. 6

B

Step-by-step explanation:

The "..." at the end of B tell us that it's a repeating decimal so B is irrational. Of course, you can't use this reasoning for every repeating decimal but in this case it works.

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: