3x/3x-1 + 2/x =1 this is the question

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.

The answer is 7.2 how would you put this as money

A0.40 kg soccer ball is kicked so that its incoming velocity of 5 m/s is changed to an outgoing velocity of -25 m/s. what impulse does the player apply to the ball?