Correct Answer: INR 7,000

Solution : Use the formula, $ \text{Marked price}= \frac{100\times \text{Selling price}}{\text {100– Discount percent }}$.
The marked price of the first article $= \frac{100\times 420}{100–30 }=\frac{100\times 420}{70}=$ INR 600
The marked price of the second article $= \frac{100\times 600}{100–25 }=\frac{100\times 600}{75}=$ INR 800
The marked price of the third article $= \frac{100\times 816}{100-32}=\frac{100\times 816}{68}=$ INR 1,200
The marked price of the fourth article $= \frac{100\times 825}{100–45 }=\frac{100\times 825}{55}=$ INR 1,500
The marked price of the fifth article $= \frac{100\times 425}{100–15 }=\frac{100\times 425}{85}=$ INR 500
The marked price of the sixth article $= \frac{100\times 800}{100–20 }=\frac{100\times 800}{80}=$ INR 1,000
The marked price of the seventh article $= \frac{100\times 840}{100–40 }=\frac{100\times 840}{60}=$ INR 1,400
The sum of the marked price of these seven articles
= INR (600 + 800 + 1200 + 1500 + 500 + 1000 + 1400) = INR 7,000.
Hence, the correct answer is INR 7,000.