What the value of 6 in the number 4.769

Can somebody me out with this question

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?

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c