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Once there were 9 children, all of which were in the same family. They were all born 18 months apart. The oldest one (George) was 5 times older than the youngest one (Michael).
How old was Michael?
How old was Michael?
Answer
3 yrs. old.If each child was born 18 months apart, then there has to be a 12 year gap between oldest and youngest.
Therefore George is 15 and Michael 3.
This is the only 12 year gap that has a difference in ages of 5 times.
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I love it. Keep 'em comin'
enjoyable.
Fun...fun is all I can say : )
I'm putting up solutions to all the algebratic questions for those who don't know how to get them:
Once there were 9 children, all of which were in the same family. They were all born 18 months apart. The oldest one (George) was 5 times older than the youngest one (Michael).
How old was Michael?
let g represent George's age, then m represent Michael's age.
Statement 1:
g = 5 * m
m = g / 5
Statement 2:
18 months = 1.5 years
g = m + 8 * 1.5
Solution:
g = (g/5) + 8 * 1.5
g = g/5 + 12
= 15 years
Therefore Michael is 3 years old
Once there were 9 children, all of which were in the same family. They were all born 18 months apart. The oldest one (George) was 5 times older than the youngest one (Michael).
How old was Michael?
let g represent George's age, then m represent Michael's age.
Statement 1:
g = 5 * m
m = g / 5
Statement 2:
18 months = 1.5 years
g = m + 8 * 1.5
Solution:
g = (g/5) + 8 * 1.5
g = g/5 + 12
= 15 years
Therefore Michael is 3 years old
Sane, you don't need algebra. Like many of the problems for which you are providing algebraic solutions, it is easier to do it without algebra.
There are 8 x 1.5 = 12 years between the youngest and oldest. 12 years is 4/5 of George's age, so George is 5/4 x 12 = 15 and Michael is 15/5 = 3.
This is actually longer than how I did it. Michael is 12 / (5-1) = 3. About two and a half seconds.
There are 8 x 1.5 = 12 years between the youngest and oldest. 12 years is 4/5 of George's age, so George is 5/4 x 12 = 15 and Michael is 15/5 = 3.
This is actually longer than how I did it. Michael is 12 / (5-1) = 3. About two and a half seconds.
This is not worded correctly. If the youngest is 3 years then 5 times 3 is 15. That would make him 15 years OLDER or 18 years. It should say he is 5 times AS OLD AS. It becomes impossible to do the mathematics in these puzzles unless the wording is accurate.
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