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An exam worth 145 points contains 50 questions. Some of the questions are worth two points and some are worth five points. How many two point questions are on the test? How many five point questions are on the test?

Respuesta :

dannielle
a*5+b*2=145     
a    +b   =50       | * -2

5a   +2b=145
-2a  -2b = -100
----------------------
5a-2a    = 145-100
3a=  45
a=45:3
a=15 questions are worth 5 p
b=50-15=35 questions worth 2 p

The number of questions that are two points and five points are respectively; 35 and 15

How to solve simultaneous equations?

Let the number of questions worth 2 points be x and let the number of questions worth 5 points be y.

The exam is worth 145 points. Thus;

2x + 5y = 145     ------(1)

There are 50 questions. Thus;

x + y = 50     -----(2)

Make x the subject of the formula in eq 2 to get;

x = 50 - y

Put 50 - y for x in eq 1;

2(50 - y) + 5y = 145

100 - 2y + 5y = 145

3y = 45

y = 15

x = 50 - 15

x = 35

Read more about Simultaneous equations at; https://brainly.com/question/16863577

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