Write a proportion to find how many points x a student needs to score on a test worth 50 points to get a test score of 78%.?/? =78/?
Accepted Solution
A:
The answer is: "39 points" . _______________________________________________________ Explanation: _______________________________________________________ " x/ 50 = 78/100 " ; in which "x" equals the number of points needed.
To solve for "x" ; _______________________________________________________
Look at the denominators: 50 * (what value?) = 100.
→ "100 ÷ 50 = 2" .
→ So; "50 * 2 = 100" ;
So, let us look at the numerators:
x * 2 = 78 ;
↔ 2x = 72 ;
Divide each side of the equation by "2" ; to isolate "x" on one side of the equation ; and to solve for "x" ; _____________________________________________ → 78 ÷ 2 = 39 ;
The answer is: "39 points" . _____________________________________________