The ratio between the three angles of a quadrilateral is 1 : 4 : 5 respectively. The value of the fourth angle of the quadrilateral is $60^∘$. What is the difference between the value of the largest and the smallest angles of the quadrilateral?
The ratio between the three angles of a quadrilateral is 1 : 4 : 5 respectively. The value of the fourth angle of the quadrilateral is $60^∘$. What is the difference between the value of the largest and the smallest angles of the quadrilateral?