Consider the following frequency distribution:

$\begin{array}{ccccccc}Class& 0-10& 10-20& 20-30& 30-40& 40-50& 50-60\\ Frequency& 3& 9& 15& 30& 18& 5\end{array}$

The modal class is

(a) 10-20 (b)20-30 (c)30-40 (d) 50-60

Consider the frequency distribution of the heights of 60 students of a class:

$\begin{array}{ccc}Height\left(incm\right)& No.of.Students& CumulativeFrequency\\ 150-155& 16& 16\\ 155-160& 12& 28\\ 160-165& 9& 37\\ 165-170& 7& 44\\ 170-175& 10& 54\\ 175-180& 6& 60\end{array}$

The sum of the lower limit of the modal class and the upper limit of the median class is :

(a) 310 (b) 315 (c) 320 (d) 330

The modal class in the following frequency distribution is:

The following is the formula for finding the mode of grouped data. State what p and q are.
Mode = $p+\frac{q-f_0}{(q-f_0)+(q-f_2)}\times h$