Hey!
Grape over total: 
After he drinks 1, there will be 1 less. That means it will be over 11
Orange over total: 
Now multiply the fractions

That means the probability is: 
Good luck and hope this helps! :)
The oldest cousin should be 10. If their ages are consecutive even whole numbers, then the younger cousins should be 2 & 4. 2+4=6+10=16
Answer:
You need to give us the answer choices