Ideas for a logic problem based on the number 80 please.

[Katherine]

My dad is about to be 80. He finds life, people and noise quite exhausting, but he's always liked logic problems. Any ideas on the theme of 80 that I can challenge him with please? Funny or serious. Thanks

 

[Dave7]

I have no idea but this is such a nice thread I have responded.
Have you tried simply googling "logic problems with the number 80" ?
Not with the number 80 in but.............there is (I am told) just one number that is divisible by all other whole numbers. By coincidence (I think) its a bible based number...........2520.
Another is........if you multiple any (and I mean ANY) number by 9 and add the resulting digits.........the answer is..........9. e.g. 9x8 = 72. 7+2 = 9
142x9 = 1,278. 1+2+7+8 = 18.........1 + 8 = 9.
Hope these help........80 is a very admirable age to reach and still be interested in such things.

 

[twentysix by twentyfive]

Interesting idea @Katherine. Need to put my thinking cap on. But write 80 in binary? Or hexadecimal? The next 80 prime numbers? There must be more interesting things tho'

 

[Rasmus]

How about this. Made for 66 but add another +14 and you get 80.

 

[jefmcg]

I'll put my thinking cap on, too.

this year 2016= 12² x 14.
and the year he was born, 1936 = 44² (or 11² x 4² or 11² x 16 if you prefer)

Just thoughts to get you started.

..there is (I am told) just one number that is divisible by all other whole numbers. By coincidence (I think) its a bible based number...........2520.

I'm not sure what this means. It's not (for example) divisible by 2519. I really can't guess what you mean.

 

[Supersuperleeds]

I'll put my thinking cap on, too.

this year 2016= 12² x 14.
and the year he was born, 1936 = 44² (or 11² x 4² or 11² x 16 if you prefer)

Just thoughts to get you started.



I'm not sure what this means. It's not (for example) divisible by 2519. I really can't guess what you mean.

It's the smallest number divisible by the numbers 1-10. The bible link is something to do with the 2520 prophecy

 

[Katherine]

I have no idea but this is such a nice thread I have responded.
Have you tried simply googling "logic problems with the number 80" ?
Not with the number 80 in but.............there is (I am told) just one number that is divisible by all other whole numbers. By coincidence (I think) its a bible based number...........2520.
Another is........if you multiple any (and I mean ANY) number by 9 and add the resulting digits.........the answer is..........9. e.g. 9x8 = 72. 7+2 = 9
142x9 = 1,278. 1+2+7+8 = 18.........1 + 8 = 9.
Hope these help........80 is a very admirable age to reach and still be interested in such things.

Thanks

 

[Katherine]

Interesting idea @Katherine. Need to put my thinking cap on. But write 80 in binary? Or hexadecimal? The next 80 prime numbers? There must be more interesting things tho'

Thanks

 

[Katherine]

How about this. Made for 66 but add another +14 and you get 80.

Thanks

 

[Katherine]

I'll put my thinking cap on, too.

this year 2016= 12² x 14.
and the year he was born, 1936 = 44² (or 11² x 4² or 11² x 16 if you prefer)

Just thoughts to get you started.



I'm not sure what this means. It's not (for example) divisible by 2519. I really can't guess what you mean.

Thanks

 

[Tim Hall]

Using Tom Lehrer, who expresses his birthday in centigrade, as a starting point, set him some similar conversions from 80.

 

[Supersuperleeds]

Put key numbers that relate to him into binary and get him to solve the list without telling him it his binary for example 80 = 1010000

you could do his birthday as xxxx/xxxxx/11110010000

 

[Katherine]

Put key numbers that relate to him into binary and get him to solve the list without telling him it his binary for example 80 = 1010000

you could do his birthday as xxxx/xxxxx/11110010000

Thanks

 

[vernon]

How about a quizz based on questions revolving around 80.
Examples

Clive Sinclair's computer **80
Who was involved in the eighty years war
Early computers used a Z80 chip. Who was the manufacturer?
Why is eighty shillings ale so called?
How many half crowns is eighty shillings?

 

[Supersuperleeds]

How about a quizz based on questions revolving around 80.
Examples

Clive Sinclair's computer **80
Who was involved in the eighty years war
Early computers used a Z80 chip. Who was the manufacturer?
Why is eighty shillings ale so called?
How many half crowns is eighty shillings?

I expected you to say name Pi to 80 decimal places






(3.1415926535897932384626433832795028841971693993751058209749445923781640628620899)