हिंदी

Express the following recurring decimal as a rational number: 51.02¯ - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Express the following recurring decimal as a rational number:

`51.0bar(2)`

योग

उत्तर

`51.0bar(2)` = 51 + 0.02 + 0.002 + 0.0002 + ...    ...(1)

These terms after the first term form a G.P. whose first term is a = 0.02 and common ratio = r = 0.1

Since |r| = |0.1| = 0.1 < 1, the sum to infinity of this G.P. exists and

S = `"a"/(1 - "r")`

= `0.02/(1 - 0.1)`

= `0.02/0.9`

= `2/90`

= `1/45`

∴ from (1), `51.0bar(2) = 51 + 1/45`

= `(2295 + 1)/45`

= `2296/45`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2: Sequences and Series - Exercise 2.3 [पृष्ठ ३३]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] 11 Standard Maharashtra State Board
अध्याय 2 Sequences and Series
Exercise 2.3 | Q 2. (iv) | पृष्ठ ३३

संबंधित प्रश्न

Find the sum to indicated number of terms in the geometric progressions 1, – a, a2, – a3, ... n terms (if a ≠ – 1).


Given a G.P. with a = 729 and 7th term 64, determine S7.


If a and b are the roots of are roots of x2 – 3x + p = 0 , and c, d are roots of x2 – 12x + q = 0, where a, b, c, d, form a G.P. Prove that (q + p): (q – p) = 17 : 15.


Find:

the 10th term of the G.P.

\[- \frac{3}{4}, \frac{1}{2}, - \frac{1}{3}, \frac{2}{9}, . . .\]

 


Find :

the 8th term of the G.P. 0.3, 0.06, 0.012, ...


Find : 

nth term of the G.P.

\[\sqrt{3}, \frac{1}{\sqrt{3}}, \frac{1}{3\sqrt{3}}, . . .\]


If the G.P.'s 5, 10, 20, ... and 1280, 640, 320, ... have their nth terms equal, find the value of n.


The product of three numbers in G.P. is 125 and the sum of their products taken in pairs is \[87\frac{1}{2}\] . Find them.


Find the sum of the following geometric progression:

2, 6, 18, ... to 7 terms;


Find the sum of the following geometric progression:

4, 2, 1, 1/2 ... to 10 terms.


Find the sum of the following geometric series:

(x +y) + (x2 + xy + y2) + (x3 + x2y + xy2 + y3) + ... to n terms;


The ratio of the sum of first three terms is to that of first 6 terms of a G.P. is 125 : 152. Find the common ratio.


Find the sum :

\[\sum^{10}_{n = 1} \left[ \left( \frac{1}{2} \right)^{n - 1} + \left( \frac{1}{5} \right)^{n + 1} \right] .\]


The sum of first two terms of an infinite G.P. is 5 and each term is three times the sum of the succeeding terms. Find the G.P.


Three numbers are in A.P. and their sum is 15. If 1, 3, 9 be added to them respectively, they form a G.P. Find the numbers.


The sum of three numbers a, b, c in A.P. is 18. If a and b are each increased by 4 and c is increased by 36, the new numbers form a G.P. Find a, b, c.


If a, b, c, d are in G.P., prove that:

\[\frac{ab - cd}{b^2 - c^2} = \frac{a + c}{b}\]


If a, b, c, d are in G.P., prove that:

(a2 + b2 + c2), (ab + bc + cd), (b2 + c2 + d2) are in G.P.


If a, b, c are in A.P. and a, b, d are in G.P., then prove that a, a − b, d − c are in G.P.


The sum of an infinite G.P. is 4 and the sum of the cubes of its terms is 92. The common ratio of the original G.P. is 


If A be one A.M. and pq be two G.M.'s between two numbers, then 2 A is equal to 


Given that x > 0, the sum \[\sum^\infty_{n = 1} \left( \frac{x}{x + 1} \right)^{n - 1}\] equals 


The product (32), (32)1/6 (32)1/36 ... to ∞ is equal to 


Check whether the following sequence is G.P. If so, write tn.

7, 14, 21, 28, …


Mosquitoes are growing at a rate of 10% a year. If there were 200 mosquitoes in the beginning. Write down the number of mosquitoes after n years.


For a G.P. If t3 = 20 , t6 = 160 , find S7


Determine whether the sum to infinity of the following G.P.s exist, if exists find them:

`1/5, (-2)/5, 4/5, (-8)/5, 16/5, ...`


Express the following recurring decimal as a rational number:

`2.3bar(5)`


Find : `sum_("n" = 1)^oo 0.4^"n"`


Select the correct answer from the given alternative.

The common ratio for the G.P. 0.12, 0.24, 0.48, is –


Answer the following:

For a G.P. a = `4/3` and t7 = `243/1024`, find the value of r


Answer the following:

Find k so that k – 1, k, k + 2 are consecutive terms of a G.P.


The lengths of three unequal edges of a rectangular solid block are in G.P. The volume of the block is 216 cm3 and the total surface area is 252cm2. The length of the longest edge is ______.


The sum or difference of two G.P.s, is again a G.P.


The sum of the infinite series `1 + 5/6 + 12/6^2 + 22/6^3 + 35/6^4 + 51/6^5 + 70/6^6 + ....` is equal to ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×