Question
The question consists of two quantities,
choose the correct option which represents the correct relation between Q1 and Q2. Quantity I: The average age of a father, mother, son, and daughter is 22.5 years. Three years hence the average age of the father and mother is 34.5 years. If the ratio of the age of son and daughter is 2:1. Find the sum of the age of Son and daughter. Quantity II: 7 years ago from the present, the ratio of the age of M and N is 6:7. Again after 5 years it is 10:11. Find the sum of teh present age of M and N .Solution
ATQ,Â
Quantity I:
Let the age of father , mother, daughter and son be F, M, D, and S.
S/D = 2 or D= S/2
The sum of the age of father , mother, daughter and son = F+M+D+S = 22.5 x 4 = 90 years
Sum of the father and mothers age after 3 years = 34.5 x 2 = 69 years
Sum of the father and mothers age at present = 69-6 = 63 years
F+M = 63 yearsÂ
S+D = 90-63 = 27 yearsÂ
3S/2 = 27Â
S= 18 years
D = 9 years.Â
S+D =27.
Quantity II:Â
Let the present age of M and N be m and n years.
Ratio of therir age 7 years ago = 6:7
(m-7)/(n-7) = 6/7
7(m-7) = 6(n-7)Â
7m-6n = 7 —-----1
(m+5)/(n+5) = 10/11
11m-10n = -5—-----2
Using 1 and 2Â
M = 25 years
N = 28 yearsÂ
M+N = 25+28 = 53 years
A dielectric placed between the plates of a capacitor increases its:
‘Lubb-dupp’ sound is produced due to the action of
What is inertia?
A coil with N turns and area A is placed in a magnetic field varying as B = B₀·e–αt. What is the induced EMF at time t = 0?
An athlete can jump farther by running before jumping due to which type of inertia?
The unit 'Weber' is associated with which of the following?
Which law is violated if two bodies in mutual gravitational interaction exert unequal forces on each other?
A ball is projected from the ground at 45°. It strikes a vertical wall and rebounds with the same speed making the same angle on the other side. If th...
________ are the elements of group 18.
Ultrasonic pulse echo technique, a non-destructive ultrasonic testing, is employed for any possible flaw detection in a metallic bar of thickness 30 cm...