She hiked 6.5 miles in total and it basically tells you she hiked 1.75 miles and 2.4 miles in the morning which equals 4.15 miles in the morning. to find how many miles she walked in the afternoon you just subtract the morning miles 4.15 from the total miles 6.5 6.5-4.15=2.35 then to find how many more miles she walked in the morning you just subtract the morning from the afternoon 4.15-2.35=1.8 miles