If there are 20 total assignments, how many points come from quizzes?

Question

There are 2 types of assignments in a world lit class, reading quizzes or vocabulary practice. Each quiz is 25 points and each practice sheet is worth 10 points. There are a total of 395 points.

Answer 1

we were given that there are 20 total assignments, and that each quiz is worth 25 points, and each sheet is worth 10 points.

 

let X = the number of quizzes, and Y = the number of sheets,

then X + Y = 20

solving for X, we get X = 20 - Y

 

Also, we know that 25X + 10Y = 395 points

 

when we substitute the value for X from the first equation, we get

25(20 - Y) + 10Y = 395

which yields 500 - 25Y + 10Y = 395

rearranging, we get 500 - 395 = 25Y - 10Y

which yields 105 = 15Y, so Y = 7

 

since Y = 7, then X  = 13

 

Proof: 7 x 10 + 13 x 25 = 70 + 325 = 395