Fractions with shapes

What is the equation of the linear function represented by the table?

During a bike challenge riders have to collect various colored ribbons each 1/2 mile they collect a red ribbon each eighth mile they collect a green ribbon and each quarter mile they collect a blue ribbion wich colors of ribion will be collected at the 3/4 markrer

Negative 5 1/12 + negative 4 1/4 + 6 3/4