How many gallons of gasoline that is 7% ethanol must be added to 2000 gallons of gasoline with 4% ethanol to get a mixture that is 5% ethanol.

1000 gallons

Step-by-step explanation:

This situation can be modelled by the following equation:

Since , and , we can rewrite the equation as follows:

Then we have to find :

Hence, 1000 gallons of gasoline that is 7% ethanol must be added.

395.84

step-by-step explanation:

2πrh+2πr²

2 (pie)(radius)(height)+2(pie)(radius)^2

1. d.90

2. e. none of these (80)

3. a. 0

4. b. 6

5. e. none of these (10)

6. a. 5