Answer is 2.35 ounces is the weight of the large envelope
Step by step
First we find the rate of change
According to the chart, For every ounce it costs .88 so .88/1 is your rate. You can call it .88 cents per 1 ounce.
So .88 x weight = cost $
Your equation is
.88w = 2.07
Divide both sides by .88 to solve for w
.88/.88 w = 2.07 / .88
w = 2.35
2.35 ounces weight of large envelope
Since we know .88 for 1 ounce, we can check our work and multiply .88 x 2.35 ounces
.88 x 2.35 = $2.07
Problem solved!