A) You divide the previous number in the sequence with 6. (31104/6 = 5184, 5184/6 = 864). Follow this pattern and you can easy find the rest.
b) You divide the previous number by 2. (14/2 = 7, 7/2=7/2)... and so on
You would do n+n+1= 575 and then you add all the n's and that's 2n + 1 = 575 them subtract 1 from 575 and then the problem would be 2n = 574 then
then you'd get 287. Get it?
The sum of the interior angles of a triangle = 180 degrees. So, all of the angles on the inside of the triangle will add up to 180.
60 + 40 + ? = 180
100 + ? = 180
? = 80
The missing angle in the triangle is 80 degrees.
Hope this helps!
Answer: the answer is -7/5