15 years ago, P was half of Q's age. If the ratio of their present ages is 6:7, what will be the pro

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31 Mar 2017 Age

15 years ago, P was half of Q's age. If the ratio of their present ages is 6:7, what will be the product of their present ages?

OPtion

1) 145
2) 210
3) 323
4) 380
5) 320
6) 378
7) 399
8) 340
9) 418
10) None of these

Solution

Answer: 378
Let the present age of P be P and Q be Q
15 Years ago
P's age P-15 and Q's age Q-15
As per question
P-15 = (Q-15)/2
=> 2P -30 = Q-15
2P- Q = 15 ---- (i)

Also its given that P/Q = 6/7
P = 6Q/7

Putting value of P in equation 1

12Q/7 - Q = 15
5Q = 15*7
Q = 21
P = 18

P*Q - 21* 18 = 378
Option 6)

Correct Option: 6 Best Solution (15)

sudhir saurav   7 years AGO

Let present age of p,q=6x,7x
15years ago,age was
6x-15=1/2(7x-15)
5x=15
X=3
Product of present age=
6x*7x
=18*21
=378years.

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Ashutosh Tiwari   7 years AGO

p:q=6:7
p/q=6x/7x
15 years ago,
p=6x-15,
q=7x-15,
p=q/2
6x-15=(7x-15)/2
x=3;
p=6*3=18;
q=7*3=21;
p*q=378;

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Bupathikavya   7 years AGO

Given
P - 15 = (Q - 15)/2
P/Q = 6/7
Solving above 2 equations we get P = 18 and Q = 21
P * Q = 18 * 21 = 378

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sirisha   7 years AGO

According to give years information 15 years ago the ratio of ages of p and Q is 1:2.
At present the ratio of their ages is 6:7
From this we can compare the difference between the ratio of their ages to the difference between the comparison of years as follows;
5----->15
1------>3
so,at present the ages of P and Q are given as
For P 6*3=18y
For Q 7*3=21y
S0,18*21=378.

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Azim Uddin Siddiqui   7 years AGO

Let the present ages of P & Q be X & Y yrs respetively.
7X=6Y
or 7X-6Y=0.........(1);
15 yrs ago 2(X-15)=Y-15
2X-Y=15.......(2)
solving eq. 1 & 2 , v get X=18 & Y= 21;
XY=378 option no.6 is the answer.

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A.P.Singh   7 years AGO

15 years ago
Q=2P

Hence (2P+15)/(P+15)= 7/6
P=3, Q=6
present ages are 18 years & 21 years
product of ages = 18*21= 378

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Sahil Mehta   7 years AGO

let the age of p = x years
let the age of q = y years
since fifteen years ago
(x-15)=1/2(y-15). eqn1
the ratio of the ages of p and q are
x/y=6/7
y= (7/6)*x eqn 2
by putting value of y from 2 in 1 we get
x=18 years
y= 21 years
the product of their ages will be 18*21 =378

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Hitesh Kumar Tiwari   7 years AGO

Let P's age = x
Q's age = y

so x = 6y/7

then

(x -15) *2 = (y -15)

solving the equation

x =18
y =21

so x *y = 18 *21
=378

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zeba faridi   7 years AGO

Let present age of P and Q be 6x and 7x resp.
ten years ago, P was half of Q's age
(6x-15)=1/2*(7x-15)
12x-30=7x-15
x=3
Prod. of their ages=6x*7x=378

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KUMAR PIYUSH   7 years AGO

As consider the age of p is x , and the age of q is y.so we have 1 equation
2{x-15}={y-15}
& 7x=6y
solving these equation we got x=18,y=21
product x*y=378

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jyothi chhabria   7 years AGO

p-15/q-15=1/2
p/q=6/7
therefore p-15/7p/6-15=1/2
p=18
&
q=21

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palak Jain   7 years AGO

Let their present ages be Pand Q respectively
A.T.Q
2P-30=Q-15
2P-Q=15..............1

Also P/Q=6/7
So,P=6/7*Q
Put this value of P in 1
we get P=18yrs and Q=21 yrs
So,18*21=378 yrs.

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Jayesh   7 years AGO

7P = 6Q
P-15 = 1/2(Q-15)
Solving this we get
Q=21
P=18
SO PRODUCT IS 378

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nikita   7 years AGO

(P-15)/(Q-15)=1/2..................(1)
P/Q=6/7.................................(2)
On solving the above two equations:
P=18 &
Q=21
Hence, P*Q=378

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Parveen Soni   7 years AGO

Let P and Q be their present age
then
2(P-15)=Q-15 -->2P-Q=15 ----(1)
and second condition-->
P/Q=6/7 which give Q=7P/6 -----(2)
from equation (1) and (2) we have -->
P=18 and Q=21 which results 18x21=378 as desired answer

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