2.62 is the answer but there’s actually way more numbers than that
lets take
x+y=100 firstly.
then x=100-y equation (i)
Now,
x-y=10
Putting value of x from equation(i)
100-y-y=10
-2y=10-100
-2y=-90
therefore, y=45
Now,
putting value of y in equation(i)
we get
x=100-45
ie x=55
hence, x=55 & y=45