SP of 20 eggs = ₹ 1 and gain = 30%
CP of 20 eggs = (1 x 100)/130 = ₹ 10/13
Now, ₹ 10/13 yields 20 eggs.

Correct Option: D

SP of 20 eggs = ₹ 1 and gain = 30%
CP of 20 eggs = (1 x 100)/130 = ₹ 10/13
Now, ₹ 10/13 yields 20 eggs.
∴ ₹ 1 will yield (20 x 13)/10 = 26 eggs
Clearly, 26 eggs were bought for ₹ 1.

Let CP = 5N and SP = 3N
Loss = (CP- SP) = (5N - 3N) = 2N

Correct Option: A

Let CP = 5N and SP = 3N
Loss = (CP- SP) = (5N - 3N) = 2N
Loss % = (2N / 5N) x 100 %
= 40%

CP of 1 toffee for 1st rate = 1/6
CP of 1 toffee for 2nd rate = 1/7
CP of 2 toffee after mixing = 1/6 + 1/7 = 13/42
CP of 1 toffee after mixing = 13/84
SP of 1 toffee after mixing = 1/6
Gain = 1/6 - 13/84 = 1/84

Correct Option: B

CP of 1 toffee for 1st rate = 1/6
CP of 1 toffee for 2nd rate = 1/7
CP of 2 toffee after mixing = 1/6 + 1/7 = 13/42
CP of 1 toffee after mixing = 13/84
SP of 1 toffee after mixing = 1/6
Gain = 1/6 - 13/84 = 1/84
Gain% = [(1/84) / (13/84)] x 100% = 100/13% = 7⁹/₁₃%

CP₁ =₹ 7500
∴ SP₁ = (7500 x 124)/100 = ₹ 9300 = CP₂
SP₂ = (9300 x 80)/100= ₹ 7440
⇒ CP₁ > SP₁
Hence, loss is incurred in this transaction
∴ Require loss = (CP₁ - SP₂)

Correct Option: C

CP₁ =₹ 7500
∴ SP₁ = (7500 x 124)/100 = ₹ 9300 = CP₂
SP₂ = (9300 x 80)/100= ₹ 7440
⇒ CP₁ > SP₁
Hence, loss is incurred in this transaction
∴ Require loss = (CP₁ - SP₂)
= 7500 - 7440
= ₹ 60

CP₁ = ₹ 4000
SP₁ = 4000 x 135/100 = ₹ 5400 CP₂
SP₂ = 5400 x 80/100 = ₹ 4320
CP₁ < SP₂
Hence, profit earned here.
∴ Required gain = ( SP₂ - CP₁)

Correct Option: B

CP₁ = ₹ 4000
SP₁ = 4000 x 135/100 = ₹ 5400 CP₂
SP₂ = 5400 x 80/100 = ₹ 4320
CP₁ < SP₂
Hence, profit earned here.
∴ Required gain = ( SP₂ - CP₁)
= 4320 - 4000 = ₹ 320