Using Algebraic Language 代數語言的應用
There are 30 multiple-choice question in a Math test.5 marks are awared for each correct answer while 1 mark is deducted for each wrong or blank answer.Suppose a student answers x questions crrectly,he will get y marks.
(a)Write down a function releting x and y.
(b)Hence,find the test mark of Shirley if she answered 20 questions correctly.
(c)If Phillip got 60 marks in the test,how many questions did he answers correctly?
吾該大家幫我計算過程,thank
Mathematics Question??
2007-11-11 4:00 am
回答 (2)
2007-11-11 4:12 am
✔ 最佳答案
(a) y = 5x + (-1)(30-x)y = 5x - 30 + x
y = 6x - 30
(b) If she answered 20 questions correctly,
y = 6(20) - 30
y = 120 - 30 = 90
She gets 90 marks.
(c) 60 = 6x - 30
90 = 6x
x = 15
He answered 15 questions
2007-11-11 4:12 am
(a) 5 * x + (-1)* (30-x) = y
5x - 30 + x =y
y = 6x - 30
(b) if she answered 20 questions correctly, i.e. x =20
Test mark = y
= 6x - 30
= 6 * 20 -30
= 90
(c) If Phillip got 60 marks in the test, i.e. y = 60
y = 6x - 30
60 = 6x -30
6x = 90
x =15
so he answers 15 questions correctly
5x - 30 + x =y
y = 6x - 30
(b) if she answered 20 questions correctly, i.e. x =20
Test mark = y
= 6x - 30
= 6 * 20 -30
= 90
(c) If Phillip got 60 marks in the test, i.e. y = 60
y = 6x - 30
60 = 6x -30
6x = 90
x =15
so he answers 15 questions correctly
收錄日期: 2021-04-13 18:12:38
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20071110000051KK03922