Question

The campus bookstore sells graphing calculators for $110 and scientific calculators for $16. On the first day of classes, 50 calculators were sold for a total of $1,646. How many of each were sold?

Answer 1

Answer: 9 graphing calculators and 41 scientific calculators were sold.

Explanation:

Let be "g" the number of graphing calculators and "s" the numbe of scientific calculators.

Set up a system of equations:

`\left \{ {{g+s=50} \atop {110g+16s=1,646}} \right.`

You can solve the system of equations using the Elimination Method. Multiply the first equation by -16, add the equations and then solve for "g":

`\left \{ {{-16g-16s=-800} \atop {110g+16s=1,646}} \right.\\.........................\\94g=846\\\\g=(846)/(94)\\\\g=9`

Substitute the value of "g" into the first equation and solve for "s":

`9+s=50\\\\s=50-9\\\\s=41`