The teacher explains, "Now take out your homework class, and answer these questions about the number you calculated for homework. Remember, it was a positive integer no more than 1000."

1 Is the number
A) Less than 100
B) Less than 900
C) Greater than 900

2 Is the sum of the digits
A) Greater than 10
B) Greater than 20
C) Greater than 30

3 Is the number divisible by:
A) 2
B) 3
C) 5

4 Are the digits:
A) Strictly increasing
B) Strictly decreasing

5 Is the number divisible by:
A) 15
B) 17
C) 19

6 If you get rid of the number's first digit, is it divisible by:
A) 19
B) 20

7 When spelled out, does the spelling use:
A) J
B) L
C) Q
D) V
E) X
F) Z

8 Ignoring the sign, what is the difference between the hundred's digit and the one's digit?
A) 2
B) 3
C) 4
D) 5

9) How many times does the letter E appear when the word is spelled out?
A) 3
B) 5
C) 7

10 Is the first digit of the number
A) Odd
B) Even

You panic, because you were too busy last night solving other things on flooble and didn't get a chance to do your homework. But when you figure out the quiz (where exactly one answer is right per question), you see that only one number will work.

What is this number?

(Note: Spelled out means in words. For example: 123 is "One hundred twenty three". Divisible means divided with no remainder. Also, padding the number with leading zeroes isn't allowed.)

6 tells us it's 3 digits.
The last 2 digits must be strictly ascending/descending and divisible by 19 or 20
_38 _20
_57 _40
_76 _60
_80
The difference between the first and last number being at least 5 gives us 9 choices
(257,357,457,876,976,320,420,520,540)
which we can narrow down because the sum of the digits need to be 10-20 (clue 2)
(257,357,457)
Test for divisibilty by 3 (clue 3)
=357
Great question Gamer - I think reading the posts gives a good insight into how different people attack the same problem (note to self; must calm down brown-nosing)

Posted by Lee on 2003-08-29 02:15:55