If x + y = 52 and x − y = 20, then what is the value of x : y?

3 : 2 3 : 4 9 : 4 7 : 5

9 : 4

x + y = 52   ---- (A) x - y = 20   ---- (B) From (A) + (B), we get  = x = 36 From (A), = y = 16 = x : y = 36 : 16 = 9 : 4