हिंदी

A Positive Number is 5 Times Another Number. If 21 is Added to Both the Numbers, Then One of the New Numbers Becomes Twice the Other New Number. What Are the Numbers? - Mathematics

Advertisements
Advertisements

प्रश्न

A positive number is 5 times another number. If 21 is added to both the numbers, then one of the new numbers becomes twice the other new number. What are the numbers?

उत्तर

Let the numbers be x and 5x. According to the question,

21 + 5x = 2(x + 21)

21 + 5x = 2x + 42

Transposing 2x to L.H.S and 21 to R.H.S, we obtain

5x − 2x = 42 − 21

3x = 21

Dividing both sides by 3, we obtain

x = 7

5x = 5 × 7 = 35

Hence, the numbers are 7 and 35 respectively.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2: Linear Equations in One Variable - Exercise 2.4 [पृष्ठ ३१]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 8
अध्याय 2 Linear Equations in One Variable
Exercise 2.4 | Q 2 | पृष्ठ ३१

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Sum of the digits of a two digit number is 9. When we interchange the digits it is found that the resulting new number is greater than the original number by 27. What is the two-digit number?


Hasan buys two kinds of cloth materials for school uniforms, shirt material that costs him Rs 50 per metre and trouser material that costs him Rs 90 per metre. For every 2 meters of the trouser material he buys 3 metres of the shirt material. He sells the materials at 12% and 10% profit respectively. His total sale is Rs 36660. How much trouser material did he buy?


Aman’s age is three times his son’s age. Ten years ago he was five times his son’s age. Find their present ages.


Arjun is twice as old as Shriya. Five years ago his age was three times Shriya’s age. Find their present ages.


The digits of a two-digit number differ by 3. If the digits are interchanged, and the resulting number is added to the original number, we get 143. What can be the original number?

The digit in the tens place of a two-digit number is 3 more than the digit in the units place. Let the digit at units place be b. Then the number is ______.


In a 2 digit number, the units place digit is x. If the sum of digits be 9, then the number is (10x – 9).


A and B are together 90 years old. Five years ago A was thrice as old as B was. Hence, the ages of A and B five years back would be (x – 5) years and (85 – x) years respectively.


Sum of the digits of a two-digit number is 11. The given number is less than the number obtained by interchanging the digits by 9. Find the number.


After 12 years, Kanwar shall be 3 times as old as he was 4 years ago. Find his present age.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×