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A Family for the Record Books

by Derek Stump

Imagine being 75 years old… and still being the baby of the family. That’s what life is like for Eugenia D’Cruz, who has 11 older brothers and sisters! The D’Cruz family set the world record for largest combined age of 12 siblings. If you add up all their ages, the sum is more than 1,000 years! On top of that, they set the record on December 15. And guess what – every day since then, they’ve all gotten a little older, so the total is even more now.

Wee ones: How many siblings – brothers and/or sisters – do you have? Is that more or less than 12?

Little kids: If 9 of the 12 siblings are sisters, how many are brothers? Try counting up from 9. Bonus: Normally a pizza is split into 8 slices. If the siblings cut their pizza into 12 slices so they each get a slice, how many more slices is that than 8?

Big kids: The oldest sibling, Doreen, is 22 years older than Eugenia, who’s 75. How old is Doreen? Bonus: Every day the siblings add 12 days to their combined age. How many (whole) days does it take to add at least 100 days to their combined age?

The sky’s the limit: If the combined ages of the 12 siblings add up to 1,044 years, what is the average age of the siblings?

 

 

 

Answers:

Wee ones: Different for everyone, but most of you probably have fewer than 12 siblings!

Little kids: 3 are brothers. Bonus: 4 more slices, because 12 – 8 = 4.

Big kids: Doreen is 97 years old! Bonus: 9 days will add 108 days to their combined age. 8 days add only 96 total.

The sky’s the limit: The average age is 87 years. You can do the long division of 1,044 / 12…or you can do it in pieces: dividing by 12 (which is 2 x 2 x 3) is like dividing by 2, then by 2 again, then by 3. 1/2 of 1044 is 522, then 1/2 of that is 261. We can see that’s a multiple of 3 because the digits add up to a multiple of 3 (2+6+1=9). The answer is exactly 87.

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