Answer:

Step-by-step explanation:
Let
denotes number of pencils, markers, erasers respectively.
For Andrea:

For Justin:

For Virginia:

On subtracting equations (i) and (ii), we get

Put
in equation (i)

Put
in equation (iii)

Multiply equation (iv) by 5 and equation (v) by 6 and then subtract both the equations.

Put
in equation 

Put
in equation (i)

The answer is .35 not 3.5
Answer:

Step-by-step explanation:
Https://www.symbolab.com/solver/function-range-calculator
this should help
Answer:
10 months
Step-by-step explanation:
my answer is 10 months because i added 30 and 18 together to get 1.6666666666666667 then i divided by 6, because i added 1 and 5 together, and got 10.