Solution -
SP of 20 kg sugar = Rs. 400
SP of 1 kg sugar = 400/20
= Rs. 20
A customer asks 20% discount.
SP of 1 kg sugar = Rs. 20
SP of 1 kg sugar after discount = 20 × (80/100)
= Rs. 16
If he gives 4% less sugar.
SP of 960 g = 960/50 (1000g = 20, 1g = 1/50 )
= Rs. 19.2
Discount = Rs. 19.2 - Rs. 16
= Rs. 3.2
So,
Effective discount = (3.2/19.2) × 100
= 100/6
= 16.66%
Therefore,
The effective discount that customer gets = 16.66%
Hence,
The correct answer is option (b) 16.66%.
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