Work Step by Step
The total number of goals is 4*14=56. Letting x be the number of goals you must score, the average would be (56+x)/15. This must be greater than 4, so the equation is (56+x)/15>4. Multiplying by 15 gives 56+x>60. Subtracting 56 from both sides is x>4. Thus, 5 is high enough.