Answer:
5
Step-by-step explanation:
We start by seeing how many families we have in total, which is 20. We then must subtract the number of families with girls only, the number of families with both boys and girls, and the number of families with no children. 20 - 7 is 13, then 13 - 8 is 5, and 5 - 0 is 5.
For this case we must simplify the following expression:

We apply distributive property on the left side of the equation:

We subtract 3n from both sides of the equation:

We subtract 6 from both sides of the equation:

We divide between 45 on both sides of the equation:

Answer:

Order is operation is PEMDAS which means Parentheses, Exponents Mulitiplication,division,Addition and Subtraction so you follow the order whether they exist or not.
So (41-3^2)-(4+4)=
41-9-8 = 32-8 = 24
37 1/2. Since the decimal is in the tens place, the best, and easiest, denominator to use is 10, which results in 37 5/10 which then can be simplified into 37 1/2