A math student goes to an office supply store and purchases a total of 16 spirals and pencils. Each spiral costs $3. 50, and each pencil costs $1. 25. If the student spent a total of $29, how many pencils did the student purchase?.

Sagot :

The student purchase 12 pencils

  • Let the total number of pencils purchased be x
  • Let the total number of spirals purchased be y

If a math student goes to an office supply store and purchases a total of 16 spirals and pencils, then;

x + y = 16 .................. 1

If each spiral costs $3. 50, and each pencil costs $1. 25 and the student spent a total of $29, hence;

1.25x + 3.5y = 29 ................. 2

Solve both equations simultaneously

x + y = 16 .................. 1 * 1.25

1.25x + 3.5y = 29 ................. 2 * 1

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1.25x + 1.25y =  20.

1.25x + 3.5y = 29

Subtract both equations

1.25y - 3.5y = 20 - 29

-2.25y = -9

y = 9/2.25

y = 4

Substitute y = 4 into equation 1:

x + y = 16

x = 16 - 4

x = 12

This means that the student purchase 12 pencils

Learn more on simultaneous equations here: https://brainly.com/question/15165519