There Are 3 First Grade Children, 5 Second Grade Children $\frac { 5 } { 7 }$

Multiple Choice

There are 3 first grade children, 5 second grade children, and 7 third grade children in a room. When choosing two children, what is the conditional probability of choosing a
Second grade child, given that either a first or a third grade child was chosen first?

A) $\frac { 5 } { 7 }$
B) $\frac { 1 } { 3 }$
C) $\frac { 2 } { 7 }$
D) $\frac { 5 } { 14 }$