Question

Помогите решить пропорцию:

( 2/3 + х ) : 14 = ( 3/2 + х ) :18

( 5х - 12 ) : 3/8 = 12,5 : 1целая 9/16

 

 

 

 

Answer 1

1)(2/3+x)•18=(3/2+х)•14
2/3•18+18x=3/2•14+14x
12+18x=21+14x
18x-14x=21-12
4x=9
X=9:4=2,25
2)(5x-12)•1 9/16=3/8•12,5
(5x-12)•25/16=3/8•125/10
5x•25/16-12•25/16=3/8•125/10
125x/16-75/4=75/16
125x/16=75/16+75/4
125х/16=75/16+150/16
125x/16=225/16
X=225/16:125/16=225/16•16/125==9/5=1,8