Decide whether the data provided in the statements numbered I and II is sufficient to answer the given question.
Question:
What is the ratio of boys to girls in a class?
Statements:
I. There are 20 boys in the class.
II. The ratio of girls to the number of students in the whole class is 3:7.

Correct option is C

Statement I:
Provides the number of boys (20) but gives no information about the number of girls or the total number of students.
This is not sufficient to calculate the ratio of boys to girls.
Statement II:
States that the ratio of girls to total students is 3:7.
From this, we can determine:
Girls = 3/7 × Total Students.
Boys = Total Students - Girls.
Thus, the ratio of boys to girls can be calculated.
This is sufficient to find the ratio.