I’d say 21 and -1 :)
21 * -1 = -21
21 - 1 = 20
28. Each person will get 2 pieces. 1/6=2/12
29. Each teacher will get 9 cookies. 1/4=(sorry, I'm not sure)
30. Each student will get 4 slices.1/16=4/64
31. She has made five.
Hope this helped :)
Answer:

Step-by-step explanation:
Hello,
let s assume that m+n is different from 0
we have this equation and we need to find m as a function of t, s, and n

<=>

for t-s different from 0, so t different from s
hope this helps
Given that <span>a bag contains 26 tiles marked with the
letters A through Z.
The probability of picking a letter from the name JACK is 4 / 26
The probability of picking a letter from the name BEN is 3 / 26.
Therefore, the probability of picking a letter from
the name JACK or from the name BEN iis given by 4 / 26 + 3 / 26 = 7 / 26 </span>
the answer that I came up with is (c)