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a math test has a total number of 120 points with 44 questions on the test. Questions are worth one, three, or five points. The number of three-point questions is ten less than twice the number of one-point questions so how many five-point questions are on the test?

Respuesta :

Answer: 9 5pt questions

Step-by-step explanation:X+Y+Z=44

1X+3Y+5Z= 120

Y=2X-10

X+3(2X-10)+5Z= 120 X+6X+5Z= 120. 7X+5Z= 120. Multiply top row by -3

X+2X-10+Z=44. 3X-10=44. 3X+Z= 54. Multiply bottom row by 7

-21X-15Z= -450

21X+7Z=378

-8z= -72

Divide by -8

z=9

15 one pt questions+ 20 3 pt + 9 5 pt = 120 pts

15+20+9=44 questions

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