Advertisements
Advertisements
Question
Three years ago, a man was 5 times the age of his son. Four years hence, he will be thrice his son's age. Find the present ages of the man and his son.
Advertisements
Solution
Let the present age of the man be M years and his sons age be S years.
Then, as per the question description,
M - 3 = 5 (S-3 ) ...... (i)
M + 4 =3 (S+4 ) ...... (ii)
From (i), we get: M + 12 = 5 S
⇒ S = `("M" + 12)/5` .........(iii)
From (ii), we get: M - 8 = 3S
Putting (iii) above, we get: M - 8 = `(3 (M + 12))/5`
⇒ 5M - 40 = 3M + 36
⇒ 2M = 76
⇒ M =38 years and hence, S= 10 years
APPEARS IN
RELATED QUESTIONS
Solve for x :
`1/(x + 1) + 3/(5x + 1) = 5/(x + 4), x != -1, -1/5, -4`
`x^2+8x-2=0`
The sum of a natural number and its square is 156. Find the number.
Solve the following quadratic equations by factorization: \[2 x^2 + ax - a^2 = 0\]
Solve the following quadratic equations by factorization: \[\frac{2}{x + 1} + \frac{3}{2(x - 2)} = \frac{23}{5x}; x \neq 0, - 1, 2\]
Solve equation using factorisation method:
(x + 3)2 – 4(x + 3) – 5 = 0
Solve equation using factorisation method:
`5/("x" -2) - 3/("x" + 6) = 4/"x"`
The speed of an express train is x km/hr arid the speed of an ordinary train is 12 km/hr less than that of the express train. If the ordinary train takes one hour longer than the express train to cover a distance of 240 km, find the speed of the express train.
Solve for x:
`(x + 1/x)^2 - (3)/(2)(x - 1/x)-4` = 0.
A boat can cover 10 km up the stream and 5 km down the stream in 6 hours. If the speed of the stream is 1.5 km/hr. find the speed of the boat in still water.
