Subject
Quantitative Aptitude
Topic
Percentage
If 75% students in a class answered the first questions on a certain test correctly. 55% answered the second question on the test correctly and 20% answered neither of the questions correctly. What percentage of students answered both the questions correctly?
If 75% students in a class answered the first questions on a certain test correctly. 55% answered the second question on the test correctly and 20% answered neither of the questions correctly. What percentage of students answered both the questions correctly?
ক)
10খ)
24গ)
44ঘ)
50Explanation
here, if number of student is 100 1st question answered correctly = n(F)= 75 2nd " " " = n(S)= 55 neither " " " = n(FUS)' = 100-20=80 Both question answered correctly = n(F∩S)=? n(FUS)= 100- n(FUS)'=100-20 =80 here, n(FUS)= n(F) +n(S)-n(F∩S) or,n(F∩S)=75+55-80 =50Related questions
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