Given that the amount of red paint and the amount of yellow paint needed to make tangerine, are:

• You know that Gavin expects to have a total of:

Since:

You know that the amount he expects to have is:

Knowing that:

Therefore:

Hence, you can conclude that it is a reasonable expectation.
• Given the Addition:

You can solve it as follows:
- Convert the Mixed Number to an Improper fraction by multiplying the whole number by the denominator and adding the result to the numerator. The denominator does not change:

- Use this formula for adding fractions:

Then:

In order to write the Sum as a Mixed Number, you need to:
- Divide the numerator 15 by the denominator 2.
- The Quotient 7 will be the whole number
- The Remainder 1 will be the new numerator.
- The denominator does not change.
Then:

Notice that it is close to his estimate.
Hence, the answers are:
- Gavin's expectation is reasonable.
- Estimation of the amount of paint made:

- It is close to Gavin's estimate.