a number has 4 digits.
no digits in the number are repeated.
the digit in the tens place is three times the digit in the thousands place.
the number is odd.
the sum of the digits in the number is 27.
what is the number?
I started with the 10s and 1000s place. To sum up to 27, the average value of the numbers needs to exceed 27/4 or almost 7. This leads me to reject 1 and 3 or 2 and 6 for 3 and 9. Now the last number has to be odd, but not 3, 9 or 1 (because it is too small).
This left me with 3x9x. If I put 5 in the ones column, I would need 10 in the hundreds column to = 27. Therefore I chose 7.
This left me with 3x97. To equal 27, 8 would fit into the hundreds column, giving me 3897.
I hope giving these steps will help you to solve similar problems in the future. Thanks for asking.
2 answers
Question 1
In a recent survey of two popular best-selling books, two-fifths of the 2,200 polled said they did not enjoy the second book, but did enjoy the first book. Of those, 40% were adults over 18. If three-eighths of those surveyed were adults over 18, how many adults over 18 did NOT report that they enjoyed the first book but not the second book?