What is 2 less than a number

Ataxi company charges $2.25 for the first mile and then $0.20 per mile for each additional mile, or f = $2.25 + $0.20(m - 1) where f is the fare and m is the number of miles. if juan's taxi fare was $6.05, how many miles did he travel in the taxi? if juan's taxi fare was 7.65, how many miles did he travel in taxi

If you answer 2+2 you will get over 80 points

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.