Ages Of Descendents

Let $x,y,z$ be the ages of my grandson, my son, and me.

Then,
$x+y+z = 120,$
$7x = y,$
$12x = z.$

Substituting the values from the second and third equations into the first gives $x+7x+12x = 120,$ so $20x=120,$ and $x=6.$

Thus, my age is $6\cdot 12 = 72.$

x+7x+12x=120 so 12x=72

my age=x years gand son ag=x/12 years son age=7x/12 years x+x/12+7x/12=120 x=72

let the age of grand son be x years then my son's age is 7 times and my age is 12 times of the age of the grand son. further the sum x + 7x + 12x = 120 this gives x= 6, and my age will be 12 times 6 and the answer is 72 years

ok. this was my solution.

let:

  X--grand son

  Y--son

   Z--my age(grand father)

eqn's:

Y=6X; where 6 came from no. of days in a week ---eqn.1

Z=12X;where 12 came from the no. of months in a year ---eqn. 2

120=X+Y+Z ---eqn. 3

solt'n:

substitute the values and solve for the value of X where it was a grand son.

120=X+7(X)+12(X)

therefore; X=6

for my age(grand father)

Z=12(X)

=12(6)

=72

therefore the age of grandfather is 76yrs.old

let the age of the grandson in years be x. thus the age of the grandpa is 12x years. and age of the father is ((365 x 7)/365)=7x years. hence 12x+7x+x = 120 and hence x is 6 years and the age of the grandpa is 72yrs

let x = grandson y = son z = my age

x + y + z = 120

x = y/7

y = 7x

x = z/12

z = 12x

x = 120 - y - z

x = 120 - 7x - 12x

x = 120 - 19x

19x + x = 120

20x = 120

x = 6 (grandson)

y = 7(6) = 42 (son)

z = 12(6) = 72 (my age)

6 + 42 + 72 = 120

120 = 120

According to the question, the equations formed are....

365x=52y

12x=z

x+y+z+=120

Adding equation 1,2---------- 377x-52y-z=0

Adding equation formed above & 3, i.e., 377x-52y-z=0 +
52(x+y+z)=(52)120

429x+51z=6240

And further using (adding) equation 2 with this result.... 429x+51z=6240 +
51(12x-z)=51(0)

1041x=6240

Therefore, x=6240/1041 = 5.99.... ≈ 6

From equation 2, we get that z=12x

So, z=12 6 = 72*

It looks like an odd one, but simple!!!

Solution: 72 years old. Let m be my age in years. If s is my son's age in years, then my son is 52s weeks old. If g is my grandson's age in years, then my grandson is 365g days old. Thus, 365g = 52s. Since my grandson is 12g months old, 12g = m. Since my grandson, my son and I together are 120 years, g + s + m = 120. The above system of 3 equations in 3 unknowns (g, s and m) can be solved as follows. m / 12 + 365 m / (52 x 12) + m = 120 or 52 m + 365 m + 624 m = 624 x 120 or m = 624 x 120 / 1041 = 72. So, ans 72 years old.