Statistics · Mean and variance
Let the mean and the variance of seven observations 2, 4, , 8, , 12, 14, , be 8 and 16 respectively. Then the quadratic equation whose roots are and is:
- (1)
- (2)
- (3)
- (4)
Video solution coming soon
We're animating every PYQ step by step. Subscribe to get them first.
See the full 6 Apr 2026, Shift 2 paper
More on Mean and variance
- 21 Jan 2026, Shift 1 · Q13Let the mean and variance of 7 observations 2, 4, 10, x, 12, 14, y, x > y, be 8 and 16 respectively. Two numbers are chosen from 1, 2, 3,…
- 23 Jan 2026, Shift 1 · Q13Let the mean and variance of 8 numbers -10, -7, -1, x, y, 9, 2, 16 be 72 and 293/4, respectively. Then the mean of 4 numbers x, y, x + y +…
- 24 Jan 2026, Shift 1 · Q18The mean and variance of a data of 10 observations are 10 and 2, respectively. If an observation α in this data is replaced by β, then the…
- 2 Apr 2026, Shift 2 · Q9The mean and variance of n observations are 8 and 16, respectively. If the sum of the first (n-1) observations is 48 and the sum of…