C.I. = [4000 * (1 + 10/100)² - 4000] = (4000 * 11/10 * 11/10 - 4000) = Rs. 840. Sum = (420 * 100)/(3 * 8) = Rs. 1750

Let the sum be Rs. P. Then,  [P(1 + 10/100)² - p] = 525 P[(11/10)² - 1] = 525 P = (525 * 100) / 21 = 2500 Sum = Rs. 2500 So, S.I. = (2500 * 5 * 4)/100 = Rs. 500

P(1 + R/100)⁵ = 2P => (1 + R/100)⁵ = 2 Let P(1 + R/100)ⁿ = 8P => (1 + R/100)ⁿ = 8 = 2³ = {(1 + R/100)⁵}³ => (1 + R/100)ⁿ = (1 + R/100)¹⁵ => n = 15
Required time = 15 years.

Principal = (P.W. of Rs. 882 due 1 year hence) + (P.W. of Rs. 882 due 2 years hence) = [882/(1 + 5/100) + 882/(1 + 5/100)²] = (882 * 20)/21 + (882 * 400)/441 = Rs. 1640.

P(1 + 20/100)ⁿ > 2P or (6/5)ⁿ > 2 Now, (6/5 * 6/5 * 6/5 * 6/5) > 2. So, n = 4 years.

Let each installment be Rs. x. Then, x/(1 + 5/100) + x/(1 + 5/100)² = 1025
820x + 1025 * 441x = 551.25So, value of each installment = Rs. 551.25

[15000 * (1 + R/100)² - 15000] - (15000 * R * 2)/100 = 96 15000[(1 + R/100)² - 1 - 2R/100] = 96 15000[(100 + R)² - 10000 - 200R]/10000 = 96 R² = (96 * 2)/3 = 64 => R = 8 Rate = 8%

S.I = Rs(5000 — 10/100 — 3)=Rs 1500 

                          = Rs (6655-5000)=Rs 1655 
(c.I) “ (S.I) = Rs (1655-1500) = Rs 155.

S.I = Rs(8000 × 5/100 ×3) = Rs 1200 
C.I = Rs [8000 × (1+5/100)³- 8000 
= Rs [(8000 × 21/20×21/20×21/20)-8000]
=Rs (9261-8000)=Rs 1261 
 (c.I)-(S.I) = Rs (1261 “ 1200) = Rs61.

P = Rs 16000, R = (10/2)% 
Per half-year , t= 4 half-years 
Therefore Amount = Rs [16000 × (1+5/100)⁴] 
= Rs (16000 × 21/20 × 21/20 × 21/20 × 21/20)
= Rs 1448.10 ~ Rs 19448