You should add each individual 'part' of the ratio and divide $26,000 by that number.
2:3:3:5
2 + 3 + 3 + 5 = 13
26000 / 13 = $2000.
Now that you have one part, you can find the largest number of dollars by multiplying it by 5, seeing as that is the partner with the largest number of parts.
$2000 * 5 = $10000.
The answer is $10000.