Explanation:

For total cookies produced pie chart
2N% + (N + 5)% + N% + (N + 20)% = 100%
(5N + 25) % = 100%
5N = 75
N = 15
Let total cookies produced by all four companies = 100x
So, total cookies produced by A = 100x ×(15+5)/100 = 20x
Total cookies produced by B = 100x × 15/100 = 15x
Total cookies produced by C = 100x ×(15+20)/100 = 35x
Total cookies produced by D = 100x ×2×15/100 = 30x
Similarly, for total chocolate cookies produced pie chart
(M + 10) % + M% + 20% + 40% = 100%
(2M + 70) % = 100%
2M = 30 ⇒ M = 15

Let total chocolate cookies produced by all four companies = 100y
So, total chocolate cookies produced by A
= 100y ×15/100=15y
Total chocolate cookies produced by B = 100?? ×20/100=20y
Total chocolate cookies produced by C = 100y ×40/100=40y
And total chocolate cookies produced by D = 100y ×(15+10)/100 = 25y
Give,
20x – 15y = 110
Or, 4x – 3y = 22 ---------- (i)
And, 15x – 20y = 30
3x – 4y = 6 --------- (ii)
From (i) and (ii) we get –
x = 10, y = 6

Total butter cookies produced by company C = (35 ×10− 40 ×6) = 110

Total butter cookies produced by D = (30 ×10−25 ×6)=150
Total revenue got by company C= 110 ×60/100 ×12=792
Total revenue got by company D= 150 ×80/100 ×15=1800
Required percentage = (1800−792)/1800 ×100=56%