→ a2515125:答案為B 09/05 23:52
During a 40-mile trip, Marla traveled at an average speed of x miles per hour
for the first y miles of the trip and at an average speed of 1.25x miles
per hour for the last 40 - y miles of the trip. The time that Marla took
to travel the 40 miles was what percent of the time it would have taken her
if she had traveled at an average speed of x miles per hour for the entire
trip?
(1) x = 48
(2) y = 20
請問這題如何列公式？
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 220.129.141.123