Math answers .if you take a test with 1 0questions and got 7 of them right, what decimal part would that be? what decimal part did you get wrong? ? explain

Right decimal percentage:  If i take a test with 10 question and i got 7 of then right the decimal would be 0.7 in percent it would be 70%. That i your answer. (this is how much you got right.) 

wrong decimal percentage:  the wrong decimal percentage would be 0.3 because divide 7 by 10 and you get 0.7 and out of 10 would be 0.3, there is your answer.

I got .7 or .70 correct. Because 7/10=.70. I got .3 or .30 wrong because .70 is 70 out of 100. 100-70=30

C. i believe it is (5×(-20))+(100×(0.7))