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