Count on or back to solve number problems to 100

Walt: Count on or back to solve number problems to 100

 

                                    today my maths group had to do Count on or back to solve number
                                    problems. and for my answer that says problem one, I did 12 because
                                    3 - 15 = 12 and problem two is 11 - 7 = 4 and number three is 17 - 9 = 8
                                    because if you count backwards from 17 like this, 16 , 15,14,13,12,11,10,9,8                                     and then it equals 8 so now do you get the answer.