Question

My grandson is about as many days as my daughter in weeks, and my grandson is as many months as i am in years. My grandson, my daughter and I together are 120 years. Can you tell me my age in years?

Answer 1

80 years , right answer?

Answer 2

this is question of linear equations in three variables
g = grandson's age
s = son's age
m = my age

"My grandson is about as many days as my son is weeks,"
s = 7g

my grandson is as many months as I am in years.
m = 12g

g + s + m = 120
Substitute for m and s
g + 7g + 12g = 120
20g = 120
g = 6 yrs is grandson's age
then
s = 7(6) = 42 yrs is son's age
and
m = 12(6) = 72 yrs is my age


See if we can prove this:
"My grandson is about as many days as my son is weeks," a
g: 6×365 = 2190 days
s: 42×52 = 2184 days, that's why they said "about"
:
"my grandson is as many months as I am in years."
g: 12×6 = 72 months 

So I am 72 year old....answer