(1/4 × n):50 =120:24

(1/4 × n) : 50 = 120 : 24
1/4 n : 50 = 5
1/4 n = 5 × 50
1/4 n = 250
n = 250 : 1/4
n = 250 × 4/1
n = 1000/1
n = 1000