Tell me a equivalent ratio for 5/45

Cassie is traveling 675 miles today to visit her brother and his family. so far, she has stopped for gas three times. at the first stop, she put in 7.1 gallons of gas and paid $23.79. at her second stop, she put in 5.8 gallons of gas and paid $19.08. and, at the third stop, 6.6 gallons and paid $20.39. at which stop did casey pay the most for gas?

Need this asap if anyone can i would be very grateful. if you could show workings that would really

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41