English

A natural number, when increased by 12, equals 160 times its reciprocal. Find the number.

Advertisements
Advertisements

Question

A natural number, when increased by 12, equals 160 times its reciprocal. Find the number.

Sum
Advertisements

Solution

Let the natural number = x

When the number increased by 12 = x + 12

Reciprocal of the number = `1/x`

According to the question, we have,

x + 12 = 160 times of reciprocal of x

x + 12 = `160/x`

x(x + 12) = 160

x2 + 12x – 160 = 0

x2 + 20x – 8x – 160 = 0

x(x + 20) – 8(x + 20) = 0

(x + 20)(x – 8) = 0

x + 20 = 0 or x – 8 = 0

x = – 20 or x = 8

Since, natural numbers cannot be negative.

The required number = x = 8

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Quadatric Euation - Exercise 4.4 [Page 42]

APPEARS IN

NCERT Exemplar Mathematics Exemplar [English] Class 10
Chapter 4 Quadatric Euation
Exercise 4.4 | Q 3 | Page 42

RELATED QUESTIONS

Solve the following quadratic equation for x4x2  4a2x + (a4  b4) =0.


Solve the following quadratic equations by factorization:

9x2 − 3x − 2 = 0


Solve the following quadratic equations by factorization:

`x^2-(sqrt2+1)x+sqrt2=0`


Solve the following quadratic equations by factorization:

ax2 + (4a2 − 3b)x − 12ab = 0


Solve the following quadratic equations by factorization:

`7x + 3/x=35 3/5`


Some students planned a picnic. The budget for food was Rs. 500. But, 5 of them failed to go and thus the cost of food for each member increased by Rs. 5. How many students attended the picnic?


Solve the following quadratic equations by factorization: \[\frac{16}{x} - 1 = \frac{15}{x + 1}; x \neq 0, - 1\]


In the following determine the set of values of k for which the given quadratic equation has real roots: \[2 x^2 + x + k = 0\]


The values of k for which the quadratic equation  \[16 x^2 + 4kx + 9 = 0\]  has real and equal roots are

 

Solve the following equation:  `"m"/"n" "x"^2 + "n"/"m" = 1- 2"x"`


Solve the Following Equation : x2- x - a (a + 1) = o 


Let ∆ ABC ∽ ∆ DEF and their areas be respectively, 64 cm2 and 121 cm2. If EF = 15⋅4 cm, find BC.


Some students planned a picnic. The budget for the food was Rs. 480. As eight of them failed to join the party, the cost of the food for each member increased by Rs. 10. Find how many students went for the picnic.


Solve the following quadratic equation by factorisation:
(2x + 3) (3x - 7) = 0


Solve the following equation by factorization

3(y2 – 6) = y(y + 7) – 3


Solve the following equation by factorization

2x2 – 8x – 24 = 0 when x∈I


Solve the following equation by factorization

`4sqrt(3)x^2 + 5x - 2sqrt(3)` = 0


Solve the following equation by factorization

`(2)/(x^2) - (5)/x + 2 = 0, x ≠ 0`


The sum of two numbers is 9 and the sum of their squares is 41. Taking one number as x, form ail equation in x and solve it to find the numbers.


If x4 – 5x2 + 4 = 0; the values of x are ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×