Answer:
yes, no, no, yes, no
Explanation:
10:40 divide by 10 you get 1:4. Correct
3:7 multiply by 3 and you get 9:21. Incorrect
12:9 divide by 3 and you get 4:3. Incorrect
25:15 divide by 5 and you get 5:3. Correct
8:9 multiply by 2 and you get 16:18. Incorrect