divisibility ?

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I have a question about divisibility

Find all two digit numbers that are divisible by the product of their digits. For example, 24 is divisible by 2x4=8.there are many more two digit numbers. Find them.

Posted 215 day ago

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atta	The digit numbers that are divisible by the product of their digits are represented mostly as the even multiples of 6, which are 11, 15 = 5 * 3, 6 * 2 = 12, 6 * 4 = 24, && 6 * 6 = 36. J.C Posted 212 day ago ( 0 ) ( 0 ) Report Abuse

In a two digit number such as n=AB,A is the tens digit and B is the units digit. So n= 10A + B. The product of twe digits will be A.B. We need to find values for (A.B) that divides (10A + B). Checking 1 to 9 digits, we see that only (1.1)=1, will divide 11,(1.2)=2, will divide 12, (1.5)=5, will divide 15, (2.4)=8, will divide 24, and (3.6)=18, will divide 36. That is all.

Posted 214 day ago

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matherapist

All 2 digit numbers are divisible by the product of the 10s digit and units digit.

If you mean divsible to an iteger value with no remainder, then the easiest way is to enumerate and test.

start with the teens 11 12 13 14 15 16 17 18 19
products 1 2 3 4 5 6 7 8 9

and we find 11/1=11,12/2=6, 15/5=3

Going to higher numbers we can eliminate any numbers ending in 0, since the product would be 0 and we can't divide by zero.
so 21 22 23 24 25 26 27 28 29 31 32 33 34 35 36 37 38 39 41 42 43 44 45 46 47 478 49
product 2 4 6 8 10 12 14 16 3 6 9 12 15 18 4 8 12 16 20 24

and we find that 24/8 and 36/18 ware OK. . Note that once the product is greater than 1/2 of the two digit number, we can stop testing in that particular tens group (40's,50's , 60's etc)

So for the 80's we have 81 82 83 84 85 86 87 88 89
8 16 24 32 40 48

No values in the 80's

Posted 214 day ago

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Raeb22

36= 6x6?

Posted 214 day ago

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Question Title	I have a question about divisibility
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