I am thinking of a three digit number.It is an odd multiple of three,and the product of its digit is 24.It is larger than 15^2.what are all the numbers i could be thinking of
@e.mccormick
Well i found one 264 C: Divisible by 3, product of its digits is 24, larger than 15^2
thats a odd multiple of 3
@e.mccormick
@phi
I only know one way to solve this, and that is by brute force search if the 3 digits multiply to give 24, then they are factors of 24. List all the factors of 24 1,24 2,12 3, 8 4,6 Now examine each pair 1 , 24 break 24 into its factors again), but only the 1 digit factos 1, 3, 8 1 , 4 ,6 to be divisible by 3, the digits must sum to a number divisible by 3 only 1,3,8 works (sums to 12) now 2,12 --> 2, 1, 12 2, 2, 6 2, 3, 4 only 2,3,4 adds to a number divisible by 3 3, 8 -> 3, 1,8 repeat 3,2,4 repeat 4,6-> 4,1,6 not div by 3 4,2,3 repeat I see only the combinations 1,3,8 and 2,3,4 (in any order) we have these candidates 138 too small 183 too small 318 not odd multiple of 3 381 ****works 813 *** works 831 ***works 234 not odd mult of 3 243 **works 324 not odd mult of 3 342 not odd mult of 3 423 ***works 432 not odd mult of 3 I see 5 candidates: 243,381,423, 813, 831
oh thanks @phi
Awhs I was wrong xc
to be absolutely sure, I would write a short computer program and double check. That is why people invented computers... to solve dumb problems like this one.
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