Student: The average of 21 numbers is 25. The average of first ten numbers is 18 and the average of last ten numbers is 32. What is the middle number?\nOptions:\n(A) 195\n(B) 175\n(C) 184\n(D) 201\n(E) 188.
Another student: Let's say, hmmm...

User
The total of 21 numbers = 21X25 = 525\nThe total of first 10 and last 10 numbers is = 10 X 14+10 X 19 = 330\nSo, the middle number is (525 - 330 ) = 195 Final answer: (A).
Assistant