I'm posting one puzzle, riddle, math, or statistical problem a day. Try to answer each one and post your answers in the comments section. I'll post the answer the next day. Even if you have the same answer as someone else, feel free to put up your answer, too!
Monday, September 18, 2006
How old?
The grandson is about as many days old as the son is in weeks. The grandson is approximately as many months old as the father is in years. The ages of the grandson, the son, and the father add up to 120 years. What are their ages?
Leave your answer or, if you want to post a question of your own, send me an e-mail. Look in the about section to find my e-mail address. If it's new, I'll post it soon.
Please don't leave spam or 'Awesome blog, come visit mine' messages. I'll delete them soon after.
There are some fractional years that (as in normal conversation) I will truncate.
ReplyDeleteFather - 72
Son - 42
Grandson - 6
Using the following equations:
Y(F) + Y(S) + Y(G) = 120
Y(S) = 365/52 Y(G) (frational results)
Y(F)= 12Y(G)
Substitution yields the Grandson is just over 6 years old.
Or you could set up the ratio:
ReplyDelete1:7:12
(weeks = days means the ratio of their ages is 7:1, months = days, 12:1)
so x + 7x + 12x = 120
Both answers make sense to me.
ReplyDeleteThe father is 72, the son is 42, and the grandson is 6 years old.