Answer:
The correct answer is option B. 19
Step-by-step explanation:
Fro the figure we can see that,
the number of students across number of answers
<u>To find students correctly answered 30 more questions</u>
From the figure we get,
The number of students answered 30 to 40 questions = 10
The number of students answered 40 to 50 questions = 9
Therefore the students correctly answered 30 more questions = 10 + 9 = 19
The correct answer is option B. 19
