What is "one third of a number is 12 less than the number itself" written in a n equation but not solved?

Thomas hiked 6 miles on monday 10 miles on tuesday and 8 miles on wednesday. what is the mean value closesst to the mean number of miles over the tree day period?

10 points? me . its important ‼️‼️

In a two-digit number the units' digit is 7 more than the tens' digit. the number with digits reversed is three times as large as the sum of the original number and the two digits. find the number.