Answer: 30 dishes
Explanation:
If 1/10 of the 60 dishes are chicken, that means 6 of the dishes are chicken.
1/10 * 60 = 6
If 1/6 of the 60 dishes are beef, that means 10 dishes are beef.
1/6 * 60 = 10
If 1/3 of the 60 dishes are pork, that means 20 dishes are pork.
1/3 * 60 = 20
If you add up all the non-vegetarian options you would get 36, that means there are 24 vegetarian options.
So if Sergei doesn’t like beef or pork, we can subtract 30 dishes from the 60 dishes in total, which is 30.
That means Sergei can choose 30 dishes from this menu.
Alternative/faster way:
Add up the pork and beef fractions;
1/6 + 1/3
Common denominator
1/6 + 2/6 = 3/6
Simplify
3/6 = 1/2
Now just find half of the 60 dishes and that would be 30.
60 - 30 = 30
We still get the same answer, he can choose 30 dishes from this menu.