Question

помогите решить уравнение х*15/12=30/36 45/x=5/9

Answer 1

X * 15 / 12 = 30 / 36 
36 * 15X = 30 * 12 
540X = 360 
X = 360 :  540
X = 2/3 
----------------------------
45 / X = 5 / 9 
5X = 45 * 9
5X = 405
X = 81