This page offers a step-by-step solution to the specific question **NCERT Class 11th Mathematics - Sequence and Series | insert five numbers between 8 and 26 such that the Answer ** from NCERT Class 11th Mathematics, Chapter Sequence and Series.

Question 14

Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.

Answer

Let A1, A2, A3, A4, and A5 be five numbers between 8 and 26 such that

8, A1, A2, A3, A4, A5, 26 is an A.P.

Here, *a *= 8, *b *= 26, *n* = 7

Therefore, 26 = 8 + (7 – 1) *d*

⇒ 6*d* = 26 – 8 = 18

⇒ *d *= 3

A1 = *a* + *d* = 8 + 3 = 11

A2 = *a* + 2*d* = 8 + 2 × 3 = 8 + 6 = 14

A3 = *a* + 3*d* = 8 + 3 × 3 = 8 + 9 = 17

A4 = *a* + 4*d *= 8 + 4 × 3 = 8 + 12 = 20

A5 = *a* + 5*d* = 8 + 5 × 3 = 8 + 15 = 23

Thus, the required five numbers between 8 and 26 are 11, 14, 17, 20, and 23.

- Q:-
Find the sum of integers from 1 to 100 that are divisible by 2 or 5.

- Q:-
If the sum of three numbers in A.P., is 24 and their product is 440, find the numbers.

- Q:- Find the sum of all natural numbers lying between 100 and 1000, which are multiples of 5.
- Q:-
The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, then find the number of terms.

- Q:-
How many terms of G.P. 3, 3

^{2}, 3^{3}, … are needed to give the sum 120? - Q:-
Find the sum of all numbers between 200 and 400 which are divisible by 7.

- Q:-
Find the sum of all two digit numbers which when divided by 4, yields 1 as remainder.

- Q:-
The 4th term of a G.P. is square of its second term, and the first term is –3. Determine its 7th term.

- Q:-
The difference between any two consecutive interior angles of a polygon is 5°. If the smallest angle is 120°, find the number of the sides of the polygon.

- Q:-
If the first and the

*n*th term of a G.P. are*a*ad*b*, respectively, and if*P*is the product of*n*terms, prove that*P*^{2}= (*ab*)^{n}.

- Q:-
Solve 24x < 100, when

(i) x is a natural number. (ii) x is an integer. - Q:-
Draw a quadrilateral in the Cartesian plane, whose vertices are (– 4, 5), (0, 7), (5, – 5) and (– 4, –2). Also, find its area.

- Q:-
A point is on the

*x*-axis. What are its*y*-coordinates and*z*-coordinates? - Q:-
How many 3-digit numbers can be formed from the digits 1, 2, 3, 4 and 5 assuming that

(i) repetition of the digits is allowed?

(ii) repetition of the digits is not allowed?

- Q:-
Find the equation of the circle with centre (0, 2) and radius 2

- Q:-
Describe the sample space for the indicated experiment: A coin is tossed three times.

- Q:-
Which of the following sentences are statements? Give reasons for your answer.

(i) There are 35 days in a month.

(ii) Mathematics is difficult.

(iii) The sum of 5 and 7 is greater than 10.

(iv) The square of a number is an even number.

(v) The sides of a quadrilateral have equal length.

(vi) Answer this question.

(vii) The product of (–1) and 8 is 8.

(viii) The sum of all interior angles of a triangle is 180°.

(ix) Today is a windy day.

(x) All real numbers are complex numbers.

- Q:-
If the set A has 3 elements and the set B = {3, 4, 5}, then find the number of elements in (A×B).

- Q:-
The base of an equilateral triangle with side 2a lies along the y-axis such that the mid-point of the base is at the origin. Find vertices of the triangle.

- Q:-
A point is in the XZ-plane. What can you say about its

*y*-coordinate?

- Q:-
One die of red colour, one of white colour and one of blue colour are placed in a bag. One die is selected at random and rolled, its colour and the number on its uppermost face is noted. Describe the sample space.

- Q:-
2 boys and 2 girls are in Room X, and 1 boy and 3 girls in Room Y. Specify the sample space for the experiment in which a room is selected and then a person.

- Q:-
A wheel makes 360 revolutions in one minute. Through how many radians does it turn in one second?

- Q:-
How many 4-letter code can be formed using the first 10 letters of the English alphabet, if no letter can be repeated?

- Q:-
Find the equation of the circle with centre (–2, 3) and radius 4

- Q:-
An experiment consists of tossing a coin and then throwing it second time if a head occurs. If a tail occurs on the first toss, then a die is rolled once. Find the sample space.

- Q:-
Describe the sample space for the indicated experiment: A coin is tossed three times.

- Q:-
Describe the sample space for the indicated experiment: A die is thrown two times.

- Q:-
Find the derivative of x at x = 1.

- Q:-
The numbers 1, 2, 3 and 4 are written separately on four slips of paper. The slips are put in a box and mixed thoroughly. A person draws two slips from the box, one after the other, without replacement. Describe the sample space for the experiment.

Ashish Kumar Pathak
2018-12-18 20:17:41

Thank you so much because this solution is given me a hot hint in my mind that help me in solving a lot of problems

Krithik
2018-08-24 19:06:03

Thanks this is very helpful to me Thank u so much

Pawankumar
2018-07-26 15:36:37

Give answer in Hindi

- All Chapters Of Class 11 Mathematics

- All Subjects Of Class 11