In simple words you just find what is being added to each term in order to get the next term. Subtracting 17 by 12 you get 5, 22 minus 17 is 5 as well. Now that what is being added is found, you go by the last term given which is 27. You keep adding 5 to the number until you get to the 22nd term which would result in 117. If you would want to know the equation in order for it to be plugged in then you would use f(x)= 7+5x . You would want to use this equation instead of f(x)= 12+5x because putting 1 as x would make it equal to 17 which is NOT the first term but the second.
Use PEMDAS, the answer that I got is 19.
answer: 2 × 2 × 2 × 2 × 2 = 32
Step-by-step explanation:

You're looking for 2/9 of 3/6 which means you are solving 3/6 ÷ 2/9.
When I was in sixth grade, my teacher always said "Dividing fractions, easy as pie. Flip the second and multiply." At the time, I thought I was too old for stuff like that, but now, I'm in ninth grade, and I haven't forgotten it. If you learn one thing, learn fractions, and learn them well because they never leave.
Anyway, 3/6 ÷ 2/9 becomes 3/6 × 9/2. Another thing from my teacher: "Multiplying fractions, no big problem. Top times top over bottom times bottom." So, 3 × 9 = 27 and 6 × 2 = 12. 27/12.
To make that a mixed number, do 27 ÷ 12. 12 goes in 2 times. This is the big number in your mixed number, your coefficient. Then you have 3 left over. (12 × 2 = 24. 27 - 24 = 3.) This is your numerator. And 12 is still your denominator.
Your answer is 2 3/12, which simplifies to 2 1/4.