Respuesta :

Answer: 6 : 7

Step-by-step explanation:

18 : 21

18 and 21 can be divided by 3

which means it leaves 6 : 7

Answer:

6:7

Step-by-step explanation:

divide 18 by 3 giving 6

divide 21 by 3 giving 7.

Both 6 and 7 cannot be divided anymore and the ratios is of 6:7