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2 votes
Sammy is taking a test. Each correct question gives him 5 points and each incorrect question causes him to lose a point. He answers all 20 questions and gets a score of 64. How many questions did he answer correctly?

User Valuk
by
6.0k points

1 Answer

5 votes

Answer:14

Explanation:

figure out 5x20,, which gives you 100 points

use trial and error is my method :)

if he answered 10 correct, he would get 50 points and lose 10. this gives 40 points. its an error

we now know its between 11 right and 19 right

we continue to do this till we get it right

14 x 5 = 68. - 4 makes 64.

User Pizzaboy
by
5.7k points