To solve your question, you add all of the measurements together, set them equal to 180, solve for x, and plug x back in for whichever angle they are asking for; in this case, they want angle R
7x + 12x + 20 + 20x - 35 = 180
39x - 15 = 180
39x = 180 + 15
39x = 195
x = 5
Angle R = 12x + 20
12(5) + 20
60 + 20
80
Option C is your answer.
The probability that her first treat is jelly is 4/20. Since she eats the candy and does not replace it, the probability the second treat is jelly would be 3/19 (1 less jelly and 1 less total candies). You would then multiply (4/20) by (3/19). That is your answer.
You have to muliply it all togeather to get the exact answer. 4 times 10 equals 40 40 times 3 equals 120 then 120 times 6 equals 720 and thats the right answer