SOLUTION: In an objective test, a pupil answered 25 out of the first 30 questions correctly. After that only 3 out of 5 of his answers were correct. If he obtained a rating of 70% on the who

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Question 888143: In an objective test, a pupil answered 25 out of the first 30 questions correctly. After that only 3 out of 5 of his answers were correct. If he obtained a rating of 70% on the whole test, how many questions were there?
Found 2 solutions by JulietG, richwmiller:
Answer by JulietG(1812) About Me  (Show Source):
You can put this solution on YOUR website!
25%2F30= 83%
28%2F35= 80%
31%2F40= 78%
34%2F45= 76%
37%2F50= 74%
40%2F55= 73%
43%2F60= 72%
46%2F65= 71%
49%2F70= 70%

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
The pupil started with 25/30
then he got 3/5 of the rest
(25+3x)/(30+5x)=7/10
x=8
(25+24)/(30+40)=49/70=7/10