Q86.Let the mean and variance of four numbers 3, 7, x and y (x > y) be 5 and 10 respectively. Then the mean of four numbers 3 + 2x, 7 + 2y, x + y and x −y is ______.
What This Question Tests
This question assesses the ability to use the definitions of mean and variance to set up and solve equations for unknown values, then compute the mean of a new set of numbers.
Concepts Tested
Formulas Used
Mean = (Σxi) / n
Variance = (Σxi²) / n - (Mean)²
📚 NCERT Sections This Tests
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2.1 Two charges 5 × 10–8 C and –3 × 10–8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.
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13.2 Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units of MeV from the following data: m ( 5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
📋 Question Details
- Chapter
- Statistics
- Topic
- Mean, Variance
- Year
- 2021
- Shift
- 26 Aug Shift 2
- Q Number
- Q86
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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