Question

Pls answer it quickly with a understanding process.

Answer 1

it can be any......................

Answer 2

Assume age of grandson(G) = X yr
Age of daughter (D) = Y yr
Age of lady (L) = Z yr

Now as given sum of age of all this three is 120 yr, so
$x + y + z = 120$
Now as daughter's age in week equals to grandson's age in days we can write
$52y = 365x$
$y = 7.02x$
So approx
$y = 7x$
Now drandson's age in months equals to grandma's age in years so we can write
$z = 12x$
Now putting value of Z & Y in first equation we get
$12x + 7x + x = 120$
$20x = 120$
$x = 6yrs$
So we got age of grandson is 6 years.
Now
$y = 7 \times 6 \\ y = 42yrs$
Age of daughter is 42 years.
And lastly
$z = 12x \\ z = 12 \times 6 \\ z = 72yrs$
So age of grand ma is 72 years.

Let' s check answer
$72 + 42 + 6 = 120$
So we can see above is true so our answer is right