Answer:
40
Step-by-step explanation:
Let the number be y
-1/2 × y = -20
y = -20 ÷ -1/2
y = 20 × 2
y = 40
The set is not closed
Example:
-4 * -3 = 12 this is not a negative integer
If starting out, there are 100 marbles and Zoe pulls out a 5 and doesn't replace it, then there are 99 marbles left to choose from. So, there are 9 digits 1-10 (not including #5) making the proportion you have left 9/99 which simplifies to 1/11
The least number of classes needed for all the students to be registered in a class is 21 classes.
X=8.
Let me explain.
2x-16=0
add 16 to both sides
2x=16
divide both sides by 2
x=8
