Answer:
improper fractions are mixed numbers that can be multiplied by bottom to top like 2/4 x 4/5 so is 2 and 4 from 2/4 and 4/5 you can also do bottom to top like 2 x 5=10 and 4 x 4= 16 now you can add 10 + 16=26
Do 40 times 12 because if she can type 40 words each minute and there is 12 minutes then it would be 480
The cumcutative property of addition
Lets say the number is x so we can make an equation
If is at least 21, that means it has to be greater then or equal to it.
6+5*x>=21
You can subtract 6 from both sides
5*x>=15
Then divide both sides by 5
x>=3
You can conclude that the number is greater then or equal to 3.
The solution (400, 3, 200) is the answer to a system of equations which has three variables. Respectively, this system is expected to have three equations because it has three unknowns. So for example if your unknowns are x, y and z, then the answers will be x=400, y=3, and z=200.