It seems we have two numbers, lets call the first number x and the second number y.
The first sentence asks for a number that 3 more than a second.
This can be written as x = y+3
The second sentence says 4 times the first number IS six less than six times the second number.
This can be written as 4x = 6y - 6
Now you have a systems of equations that you can solve for using the substitution method.
Best of luck with Math, if you have further questions please be sure to send them.