3点15分时分针与时针夹角是多少?

5千克花生可榨出2点1千克花生油,要想榨出3点15吨花生油,需要多少千克花生
5:2.1 = x :3.15
x= 5x3.15/ 2.1 =7.5 吨 = 7500千克

15*6=90
15*0.5=7.5
90+7.5-90=7.5
当钟表时间为3点15分时,分针与时针所成的角是7.5度
30+7.5=37.5
6-0.5=5.5
37.5/5.5=75/11(分）

1小时就是360/30=30°
时针与12点夹角是30*3=90°
3点15=3.25小时
分针与12点夹角是3.25*3=97.5°
97.5-90=7.5
夹角是7.5°

1、90°
360°+360÷12=390°

解题思路：根据时钟3时15分时，时针在3与4中间位置，分针在3上，可以得出分针与时针的夹角是[15/60]个格，每一格之间的夹角为30°，可得出结果．

∵钟表上从1到12一共有12格，每个大格30°，
∴时钟3时15分时，时针在3与4中间位置，分针在3上，
∴分针与时针的夹角是[15/60]×30°=7.5°．
故答案为：7.5°．

点评：
本题考点： 钟面角．

考点点评： 此题主要考查了钟面角的有关知识，得出钟表上从1到12一共有12格，每个大格30°，是解决问题的关键．

∵钟表上从1到12一共有12格，每个大格30°，
∴时钟3时15分时，时针在3与4中间位置，分针在3上，
∴分针与时针的夹角是[15/60]×30°=7.5°．
故答案为：7.5°．

half one quarter past three half three quarter past two quarter to two quarter to three

上底呢

1点15 - one fifteen,a quarter pass one
3点45 - three fort-five,a quarter to four ,
1点30 - one thirty ,half pass one
3点15 - three fifteen,a quarter pass three
2点30 - two thirty,half pass two
3点30 - three thirty ,half pass three
2点15 - two fifteen,a quarter pass two
1点45 - one forty- five ,a quarter to two
2点45 - two forty-five,a quarter to three

口语化的
One thirty
Three fifteen
One forty five
另外说法
Half past one
Quarter past three
Three quarters past one

15/60×（360×1/12)=7.5
7.5度

nine thirty=half past nine
seven forty-five = a quarter to eight
one fifty-five=two to two
four forty-three=seventeen to five
three fifteen=a quarter past three
eight fifteen=a quarter past eight
10 o'clock
six twenty-five= twenty-five past six

twenty -five past five5 to 12ten past ten half past sixseven o'clocka quarter past three ten past threeten to fivetwenty-five to threea quarter to ninetenwty past nine

11点 eleven o'clock
3点15 three fifteen = a quarter past three
2点30 two thirty = half past two
3点45 three forty- five = a quarter to four
5点55 five fifty-five = five to six