In 50 numbers 10 are threes,15 are fours,18 are fives and remaining are…
2023
In 50 numbers 10 are threes,15 are fours,18 are fives and remaining are sixes.if a,b and c respectively represent the mean,mode and median of data,what is the value of a+2b-c?
- A.
10
- B.
12.65
- C.
9.94
- D.
8.34
Attempted by 33 students.
Show answer & explanation
Correct answer: C
Solution:
There are 50 numbers: 10 of value 3, 15 of value 4, 18 of value 5, and 7 of value 6.
Mean (a) = (10×3 + 15×4 + 18×5 + 7×6) / 50 = 222/50 = 4.44.
Mode (b) is the value with the highest frequency, which is 5.
Median (c): find the 25th and 26th terms in the ordered list.
Cumulative positions: 3s → 1–10, 4s → 11–25, 5s → 26–43, 6s → 44–50.
So the 25th term = 4 and the 26th term = 5; median = (4 + 5)/2 = 4.5.
Compute a + 2b − c = 4.44 + 2×5 − 4.5 = 4.44 + 10 − 4.5 = 9.94.
Answer: 9.94