Question

Gurpreet is very fond of doing research on plants. She collected some leaves from different plants and measured their lengths in mm.

The length of the leaves from different plants are recorded in the following table.$\text{Length (in mm)}$	70-80	80-90	90-100	100-110	110-120	120-130	130-140
$\text{Number of leaves}$	3	5	9	12	5	4	2
Based on the above information, answer the following questions :