Seiji and Gavin both worked hard over the summer. Together they earned a total of $525. Gavin earned $25 more than Seiji.

Seiji's earning = $250;

Gavin's earning = $275

Explanation:

Consider Seiji's earning to be $x

According to question, Gavin earned $25 more than Seiji

Then, Gavin's earning = x + $25

According to question, total earning is $525

Then, x + x + 25 = 525

Solving for x,

2x + 25 = 525

2x = 500

x = 250

Therefore, Seiji's earning, x = $ 250

Gavin's earning = 250+25 = $275