SOA Exam P Practice Q24

A car dealership offers three types of vehicles: SUVs, Sedans, and trucks. Sales records at the dealership indicate that the number of Sedans sold is one-fifth the number of SUVs and trucks combined. Records also indicate that three times as many trucks are sold as SUVs.
Calculate the probability that the next vehicle sold is either an SUV or a Sedan.
[A similar question can be found in the official SOA website: www.soa.org]