Let 2 yuan 5 yuan have a face value of x 10 yuan and a face value of Y.

X+x+y=50, so y=50-2x.

2x+5x+ 10y=240

Replace the second type with the first type.

7x+500-20x=240

x=20

So y= 10

So the number of 5 yuan in 2 yuan is 20, and the number of 10 yuan is 10.

I hope I can help you.