Let the extra money invested = ₹ P
According to the question .
(3000 x 5 x 1)/100 + (P x 8 x 1)/100 = [(3000 + P) x 6 x 1)]/100

Correct Option: C

Let the extra money invested = ₹ P
According to the question .
(3000 x 5 x 1)/100 + (P x 8 x 1)/100 = [(3000 + P) x 6 x 1)]/100
⇒ 15000 + 8P = 18000 + 6P
⇒ 2P = 18000 - 15000
∴ P = 3000/2 = ₹ 1500

Initially ,
let P = ₹ A, R = 13/2% per annum and T = 1yr
SI = PRT/100 = (A x 1 x 13/2)/100 = ₹ 13A/200

Now, new deposit = ₹ (A - 600), R = 11/2 % per annum and T = 1yr
SI = PTR/100 = [(A - 600) x 1 x 11/2)/100] = ₹ 11(A - 600)/200

By the given condition ,
13A/200 - 11(A - 600)/200 = 73

Correct Option: A

Initially ,
let P = ₹ A, R = 13/2% per annum and T = 1yr
SI = PRT/100 = (A x 1 x 13/2)/100 = ₹ 13A/200

Now, new deposit = ₹ (A - 600), R = 11/2 % per annum and T = 1yr
SI = PTR/100 = [(A - 600) x 1 x 11/2)/100] = ₹ 11(A - 600)/200

By the given condition ,
13A/200 - 11(A - 600)/200 = 73
⇒ 13A - 11(A - 600 ) = 200 x 73
⇒ 2A = 200 x 73 - 600 x 11
⇒ 2A = 14600 - 6600
⇒ 2A = 8000
∴ A = 4000

Hence, the initial investment is ₹ 4000.

Amount after 5 yr, 4200 + (4200 x 10 x 5)/100
= (4200 + 2100) = Rs 6300

Correct Option: A

Amount after 5 yr, 4200 + (4200 x 10 x 5)/100
= (4200 + 2100) = Rs 6300
∴ Cost of the cow = (6300 - 5000) = ₹ 1300

Let the principle and rate of interest be P and R%
Then, (P x R x 10)/100 = 600
⇒ PR = 6000

Correct Option: C

Let the principle and rate of interest be P and R%
Then, (P x R x 10)/100 = 600
⇒ PR = 6000
Total interest at the end of year = 300 + (3P x R x 5)/100 = 300 + (15 x 6000)/100 = ₹ 1200

Let each sum be ₹ P then,
(P x 10 x 5)/100 - (P x 10 x 4)/100 = 220

Correct Option: C

Let each sum be ₹ P then,
(P x 10 x 5)/100 - (P x 10 x 4)/100 = 220
⇒ P/10 = 220
∴ P = 2200
Hence, each sum is ₹ 2200.