Q66.If some three consecutive coefficients in the binomial expansion of (x + 1)n in powers of x are in the ratio 2 : 15 : 70, then the average of these three coefficients is: (1) 227 (2) 964 (3) 625 (4) 232
What This Question Tests
This question tests the understanding of the ratio of consecutive binomial coefficients, `nCr / nC(r-1)`. By setting up equations based on the given ratios, the values of `n` and `r` can be determined, which then allows calculation of the average of the three coefficients.
Concepts Tested
Formulas Used
nCr / nC(r-1) = (n-r+1)/r
Average = Sum/Count
📚 NCERT Sections This Tests
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
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13.4 Obtain approximately the ratio of the nuclear radii of the gold isotope 197 79 Au and the silver isotope 10747 Ag .
📋 Question Details
- Chapter
- Binomial Theorem
- Topic
- Properties of binomial coefficients
- Year
- 2019
- Shift
- 09 Apr Shift 2
- Q Number
- Q66
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 8: Binomial Theorem
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