Q76.A factory is operating in two shifts, day and night, with 70 and 30 workers, respectively.If per day mean wage of the day shift workers is, ₹ 54 and per day mean wage of all the workers is ₹ 60, then per day mean wage of the night shift workers (in ₹ ) is : (1) 75 (2) 74 (3) 69 (4) 66
What This Question Tests
This question assesses the understanding and application of the combined mean formula to find the mean of one subgroup when the overall mean and other subgroup means and sizes are known.
Concepts Tested
Formulas Used
Combined mean = (n1*mean1 + n2*mean2) / (n1+n2)
📚 NCERT Sections This Tests
9.6 — A Prism Is Made Of Glass Of Unknown Refractive Index. A Parallel
Physics Class 12 · Chapter 9
9.6 A prism is made of glass of unknown refractive index. A parallel beam of light is incident on a face of the prism. The angle of minimum deviation is measured to be 40°. What is the refractive index of the material of the prism? The refracting angle of the prism is 60°. If the prism is placed in water (refractive index 1.33), predict the new angle of minimum deviation of a parallel beam of light.
13.2 — Obtain The Binding Energy Of The Nuclei 5626Fe And 20983 Bi In Units Of
Physics Class 12 · Chapter 13
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
11.6 — The Threshold Frequency For A Certain Metal Is 3.3 × 1014 Hz. If Light
Physics Class 12 · Chapter 11
11.6 The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.
📋 Question Details
- Chapter
- Statistics
- Topic
- Mean, weighted mean
- Year
- 2015
- Shift
- 10 Apr Online
- Q Number
- Q76
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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