Answer:
18-Yes 19-No 20-yes 21- yes
Step-by-step explanation:
18
1 to 4, 5 to 20
Yes, this is correct
WE can multiply 1*5 and 4*5 to get 5 to 20
19
Wrong
3 to 11, 1 to 3 isn't correct
For example, if we were to divide 3 by 3 to get one, 11/3 is 2. (6)
So, no
20
2/3 is 2 to 3
14/21 is 14 to 21
If we multiply 2*7 and 3*7, we get 14 to 21
21 25 to 30 is equal to 35 to 42
They just added 7 to both numbers
if we divide ratio 1 by 5, we get 5:6
if we divide ratio 2 by 7 we get 5 to 6