Without indicating what money she earns there isn't enough information. We also need to know the overtime rate compared to normal working hours. Not to worry, we can use symbols. First, let's put a value, W, on how much she earns for 50 hours, which I assume includes the 10 hours overtime. Let the overtime rate be time and a quarter, which means that overtime is worth 25% more than normal time. If she works 50 hours including the overtime, she works 40 hours normal time. Remember we have been given W as a number. This doesn't tell us her normal hourly rate, so we'll call it an unknown quantity H. So W (given)=40H+10H*1.25=40H+12.5H=52.5H. Now we can work out H=W/52.5. That's the normal rate. The overtime rate is 1.25H.
Let's say the wage, W, is $1,050 for the week. H=1050/52.5=$20 per hour. The overtime rate is 1.25*20=$25 per hour. 40 hours at $20 per hour earns $800 and 10 hours' overtime earns $250, so she takes home 800+250=$1,050.