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4 votes
Ms. Smith is giving a test worth 100 points and contains 40 questions. There are two-point and four-point questions on the test.

User Cstruter
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2 Answers

3 votes

x for 2 pointquestion y for 4 point question

x+y=40

2x+4y=100

x=40-y

80-2y+4y=100

2y=100-80

2y=20

y=10

x=40-10=30

User Shadman
by
8.1k points
5 votes
Let x be the number of questions worth 2 points and y the number of questions worth 4 points.

X•2+y•4=100 points
X+ y=40 questions

X=40-y substitute in the first equation
(40-y)•2+4y=100
80-2y+4y=100
2y=100-80=20 so y=20/2=10
So x=40-10=30

There are 30 questions worth 2 points and
10 questions worth 4 points.

Verify 30•2+10•4= 60+40=100 ✔️
User Syndi
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8.7k points