Ok so I had the same problem a while back so I will tell you want to do.
Put the 5 and 7 into a fraction so 5/7
Then turn the 8 and 12 into a fraction so 8/12
Then write them together to cross multiply so 5/7=8/12
Lastly you should cross multiply the 7 and the 8 and the 5 and the 12
You should get 250/360
Answer: No because, when you check by cross multiplying, you do not get the same answer. I hope that helped!