Помогите решить) 2.1/7:b=2.19/28:3.3/4=

Question

Помогите решить) 2.1/7:b=2.19/28:3.3/4=

Answer 1

2  1/7 : х=2  19/28:3  3/4
15/7x=75*4/28*15
15/7x=300/420
2100x=6300
x=3