So if she works 640 hours we need to find out how much of that gets the 10% raise
640-400=240
So 240 hours get a 10% raise
400 • $9.50= $3,800
To find out how much the raise effects it
$9.50 • 10%= $0.95 + $9.50= $10.45
So the rates for the hours over 400 are $10.45
240 • $10.45=$2,508
$2,508 + $3,800= $6,308
So she made $6,308