Question 571516
Let the number be x and y
as per 1st condition;
x+y=135 ....(1)

and as per second condition;
2x = 280-3y
or x = (280-3y)/2 ........(2)

put the values of x from (2) into (1) and we get

[(280-3y)/2] + y = 135

solve the above equation and you get
y= 10

put the value of y in 1 and we get
x = 125

hope this will help you