A sum of ₹12,000 deposited on compound interest becomes double after 5 years. After 20 years, it will become:

₹1,92,000

12000 becomes twice in 5 years = 12000 × 2 = 24000

After another 5 years = 24000 × 2 = 48000

After another 5 years = 48000 × 2 = 96000

After another 5 years = 48000 × = 1,92,000

∴ After 20 years sum will be = 192000