(i) Mean value: 

Let’s rearrange the data:

Now, from this improved table, we have:

∑fx = 60500 and ∑f = 110

∴ Mean =

∴ Mean = = 550

Therefore, the mean value of the given grouped data is 550

(ii) Mode value:.

Since the frequency is highest in “550-600”

∴ “550-600” is the modal class

Since the mode value is calculated by = L + h

Here, L = 550, f0 = 20, f1 = 23, f2 = 22 and h = 600-550 = 50

∴ Mode = 550 + (50)

= 550 + (50)

= 550 + 37.5 = 587.5

Therefore, the mode value of the given grouped data is 587.5