Percentage problems
Answers are for parents and teachers.
1
50 000 so‘m is deposited at 20% compound interest per year for 2 years. What is the final balance in so‘m?
72000
2
9 000 000 so‘m is borrowed for 1 year at 12% simple interest, paid in equal monthly payments. How many so‘m is each payment?
840000
3
Equipment worth 12 000 000 so‘m has a 25% depreciation rate. What is its value in so‘m after 2 years?
6750000
4
A 100 000 so‘m item is worth 64 000 so‘m after 2 years. Find the yearly depreciation rate (%).
20% (because (1 − r/100)² = 0.64 ⇒ 1 − r/100 = 0.8).
5
For 1 000 000 so‘m, bank A offers 10% simple interest per year for 3 years and bank B offers 9% compound interest (yearly). Which gives more interest?
A: 300 000 so‘m; B: 1 000 000 · 1.09³ − 1 000 000 = 295 029 so‘m. A gives more.