F.4 Maths
2015-02-03 5:32 am
1.Sam makes a journey in two stages.In stage 1, he cycles at 10km/h for onehour.In stage 2, he cycles at 20km/h.(a) In stage 2, Sam cycles for x minutes. Write down a formula for S,the average speed, in km/h.(b) Your formula s a mathematical model for the average speed. Show thatit simplifies to(c) S=(600+20x)/ 60+x
回答 (1)
2015-02-03 6:03 pm
✔ 最佳答案
total distance = (10)(1) + (20)(x / 60) = (10 + x/3) kmtime used = (1 + x/60) h
S = (10 + x/3) / (1 + x/60)
S = 60[(10 + x/3)] / 60[(1 + x/60)]
S = [(60)(10) + (60)(x/3)] / [(60)(1) + (60)(x/60)]
S = (600 + 20x) / (60 + x)
參考: knowledge
收錄日期: 2021-04-28 14:22:57
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20150202000051KK00122