The marks obtained (out of 70) by 80 students in a unit test were grouped as shown below:
Inclusive distribution:
0–9 (3), 10–19 (7), 20–29 (12), 30–39 (18), 40–49 (25), 50–59 (10), 60–69 (5)
Using this information, answer the following.
a. (i) Rewrite the above distribution using continuous class boundaries.
b. (ii) Using the continuous distribution, draw a histogram on graph paper and label both axes with suitable scales.
c. (iii) From the histogram, state the modal class of the data.