5, 5, 9, 12, 18, 22, 25 put numbers in order least to greatest
25 -5 = 20 that is the range
12 is the middle number this is the median
5 is the mode, it is the number that is repeated the most
This question seems to me to be an exercise in applying the rule for a difference of squares in order to rewrite the difference of two relatively large numbers as the "simpler" product of other integers.
Answer:
The probability that a student is proficient in mathematics, but not in reading is, 0.10.
The probability that a student is proficient in reading, but not in mathematics is, 0.17
Step-by-step explanation:
Let's define the events:
L: The student is proficient in reading
M: The student is proficient in math
The probabilities are given by:


The probability that a student is proficient in mathematics, but not in reading is, 0.10.
The probability that a student is proficient in reading, but not in mathematics is, 0.17
Answer: a = 40, b = 50, c = 115
Solution:
a = 40 (the vertical angles are equal)
b = 180 - 40 - a = 50 (the sum of interior angles of triangle is 180)
c = 180 - 65 = 115 (the linear theorem)