Let initial cost of the saree be $100 for each saree.
Hence total initial cost = $300

Final cost of Yellow saree = \((1+\frac{20}{100})(1+\frac{20}{100})*100\)= 1.2*1.2*100 = $144
Final cost of Green saree = \((1-\frac{10}{100})(1+\frac{30}{100})*100\)= 0.9*1.3*100 = $117
Final cost of Red saree = \((1+\frac{30}{100})(1-\frac{20}{100})*100\)= 1.3*0.8*100 = $104

Total Final cost = 144+117+104 = $365
Difference = 365-300 = $65

Percentage difference = \(\frac{65}{300}*100\)% = \(21\frac{2}{3}\)%

Ans is C IMO

Let x be the cost of a saree.
The cost of sarees when Avani bought was 3x
The cost of sarees when Pannaat bought was 1.2x+0.9x + 1.3x=3.4x
The cost of sarees when Harsha bought was 1.2*1.2x+0.9*1.3x + 1.3*0.8x=x(1.44+1.3*1.7)=3.65x
(3.65-3)/3=65/300=13/60=21.67 C)

(A) 47.60%
(B) 30%
(C) 21 2/3%
(D) 20%
(E) 15%

Solution:

We can let the cost of each saree be $100 when Avani bought them. Thus, she sold them to Panna for $120, $90, and $130, respectively. Panna in turn sold them to Harsha for $144, $117, and $104, respectively. Therefore, Harsha bought them for a total of 144 + 117 + 104 = $365 and Avani bought them for 100 x 3 = $300. We see that the $365 is $65 more than $300, or 65/300 = 21 ⅔% more than $300.

Answer: C
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