So, missing term = 95 x 5 + 4 = 479.

Thus, if the missing term be x, then we have : 7 x x = 56 or x = 56 ÷ 7 = 8.

i.e. 2², 3², 5²,.....,

11², 13², 17², 19².

So, missing term = 7² = 49.

So, missing term = 59 x 2 + 4 = 122.

So, missing term = 108 x 3 = 324.

So, the series is an A.P. in which a - 5 and d = 3.

Let 320 be the nth term of the series.

Then, 320 = 5 + (n - 1) x 3 or (n - 1) = 105 or n = 106.

I. 1st, 4th, 7th, 10th terms i.e. 8, 7, 6, ?

II. 2nd, 5th, 8th, 11th terms i.e. 9, 10, 11, 12

III. 3rd, 6th, 9th terms i.e. 8, 9, 10 The pattern in I is - 1.

So, missing term = 6 - 1 = 5.

So, missing term = (15 x 2) + 1 = 31.

So, missing number = (10 x 3) - 2 = 28.

So, missing term = 41 + 20 = 61.