One hour after Yolanda started walking from X to Y, a distance of 40 miles, Bob started walking along the same road from Y to X. If Yolandaâs walking rate was 2 miles per hour and Bobâs was 4 miles per hour, how many miles had Bob walked when they met?	Options:
A) 24 B) 23.5 C) 22 D) 21.2 E) 25.32

Rationale: "let t be the number of hours that bob had walked when he met yolanda . then , when they met , bob had walked 4 t miles and yolanda had walked 2 ( t + 1 ) miles . these distances must sum to 40 miles , so 4 t + 2 ( t + 1 ) = 40 , which may be solved for t as follows 4 t + 2 ( t + 1 ) = 40 4 t + 2 t + 2 = 40 6 t = 38 t = 6.33 ( hours ) therefore , bob had walked 4 t = 4 ( 7.6 ) = 25.32 miles when they met . the best answer is e ."
Answer: E