From the information given, you can say that 5 marks for the number of correct answers minus two marks for the number of incorrect answers is equal to 30 that is the score that Radhika got:
(5*10)-2x= 30, where x is the number of incorrect answers.
Now, you can solve for x:
50-2x=30
50-30=2x
20=2x
x=20/2
x=10
According to this, the answer is that they attempted 10 incorrect answers.
