Advertisements
Advertisements
प्रश्न
The sum of the ages of a boy and his brother is 25 years, and the product of their ages in years is 126. Find their ages.
उत्तर
Let the present ages of the boy and his brother be x years and (25-x) years.
According to the question:
`x(25-x)=126`
⇒`25x-x^2=126`
⇒`x^2-(18-7)x+126=0`
⇒`x^2-18x-7x+126=0`
⇒`x(x-18)-7(x-18)=0`
⇒`(x-18)(x-7)=0`
⇒`x-18=0 or x-7=0`
⇒`x=18 or x=7`
⇒ `x=18` ( ∵Present age of the boy cannot be less than his brother)
If x 18,we have
Present ages of the boy = 18 years
Present age of his brother =(25-18)years=7 years
Thus, the present ages of the boy and his brother are 18 years and 7 years, respectively.
APPEARS IN
संबंधित प्रश्न
The difference of the squares of two natural numbers is 45. The square of the smaller number is four times the larger number. Find the numbers.
Three consecutive positive integers are such that the sum of the square of the first and product of the other two is 46. Find the integers.
The numerator of a fraction is 3 less than its denominator. If 1 is added to the denominator, the fraction is decreased by `1/15`
. Find the fraction
In a class test, the sum of Kamal’s marks in mathematics and English is 40. Had he got 3 marks more in mathematics and 4 marks less in English, the product of the marks would have been 360. Find his marks in two subjects separately.
A train travels at a certain average speed for a distanced of 54 km and then travels a distance of 63 km at an average speed of 6 km/hr more than the first speed. If it takes 3 hours to complete the total journey, what is its first speed?
A passenger train takes 2 hours less for a journey of 300 km if its speed is increased by 5 km/hr from its usual speed. Find its usual speed.
In a flight of 2800 km, an aircraft was slowed down due to bad weather. Its average speed is reduced by 100 km/h and time increased by 30 minutes. Find the original duration of the flight.
A train travels at a certain average speed for a distance 63 km and then travels a distance of 72 km at an average speed of 6 km/hr more than the original speed, If it takes 3 hours to complete total journey, what is its original average speed?
Write a quadratic polynomial, sum of whose zeros is \[2\sqrt{3}\] and their product is 2.
A takes 6 days less than B to finish a piece of work. If both A and B together can finish the work in 4 days, find the time taken by B to finish the work.