#### Answer

Since the area of the red upper stripe is greater than the total area of the 50 white stars, the color red occupies the greatest area on the flag.

#### Work Step by Step

We know that only 18.73% of the total area is blue.
The only difference between the white area and the red area is that the red area includes one extra red upper stripe, while the white area includes 50 white stars.
The area of the red upper stripe is $8.77~in^2$
The total area of the 50 white stars is $5.31~in^2$
Since the area of the red upper stripe is greater than the total area of the 50 white stars, the color red occupies the greatest area on the flag.