Grades 11-12 Video Solutions 2022-2022_11-12

Video Transcription

The product of the digits of a 10-digit integer is 15. What is the sum of the digits of this number?  So since the product is 15, we know that the number has to contain a 3 and a 5. But now that it contains the 3 and a 5, the product is already 15,  and that means the rest of the digits have to be all 1s. And so we have a 3 and a 5 and then 8 1s, so the sum of the digits is 3 plus 5 plus 1 times 8 is 16.  That means our answer is D.

Video Summary

The product of the digits of a 10-digit integer is 15. What is the sum of the digits of this number? So since the product is 15, we know that the number has to contain a 3 and a 5. But now that it contains the 3 and a 5, the product is already 15, and that means the rest of the digits have to be all 1s. And so we have a 3 and a 5 and then 8 1s, so the sum of the digits is 3 plus 5 plus 1 times 8 is 16. That means our answer is D.

Keywords

10-digit integer

product of digits

sum of digits

math problem

integer puzzle