Question

a) abc * 9 = 3abc

Answer 1

abcx9 = 3abc

=> abcx9 = 3000 + abc

=> abcx9 - abc = 3000

=> 8xabc = 3000

=> abc = 3000/8 

=> abc = 375

Tick nha 

Answer 2

abc x 9 = 3000+ abc
abc x 8 = 3000

abc=3000:8=375

Answer 3

abc x 9 = 3abc

abc x 9 = 3000 + abc

abc + abc x 8 = 3000 + abc

abc x 8 = 3000 (Cùng bỏ abc)

abc = 3000 : 8

abc = 375

Tick nha!!!