Mathematics Minds

Practice Problem Solving

1. Your salary has increased by 10% and then decreased by 10%. Is your final salary the same as the original?
2. A shirt is on a 30% discount, and then another 20% off is given. What is the effective discount percentage?
3. A product’s price increased by 20% and then decreased by 20%. What is the overall percentage change?
4. What is the original number if 30% of a number is added to itself, and the result is 120?
5. A rectangular garden has an area of 600 square meters. If the length is increased by 20%, what is the new area?
6. The price of a car increased by 30% and then decreased by 15%. What is the net percentage change?
7. You invested $1,000 at an annual interest rate of 5%, compounded quarterly. What is the total amount after one year?
8. The company’s profits increased by 25% and then decreased by 20%. What is the overall percentage change in profits?
9. If a company’s revenue is $200,000, and the expenses are 40% of the revenue, what is the profit margin?
10. A store offers a 10% discount on a $200 item and then gives a $20 discount. What is the final price?
11. You borrowed $5,000 at an annual interest rate of 8%. How much interest will you owe after one year?
12. The value of a house appreciated by 15% in the first year, and then depreciated by 10% in the second year. What is the net percentage change?
13. A company’s stock price increased by 12% then decreased by 8%. What is the net percentage change?
14. If a solution is 20% sugar, and another solution is 30% sugar, what ratio should they be mixed in to create a 25% sugar solution?
15. The price of a laptop is a 25% discount. If the original price is unknown, what is the minimum percentage by which the price could be?
16. The company’s market share increased by 40% and then decreased by 30%. What is the net percentage change?
17. If a rectangle has a length of 10 cm and a width of 6 cm, and both dimensions are increased by 25%, what is the new area?
18. You sold a product for $120, and the selling price was a 60% profit. What was the cost price?
19. A store offers a 15% discount on a $250 item and then gives a 10% cashback. What is the final price after cashback?
20. If 8% of a number is subtracted from itself, and the result is 92, what is the original number?
21. The company’s expenses are $80,000, representing 20% of the revenue. What is the total revenue?
22. The price of a camera increased by 10% and then decreased by $30. If the final price is $270, what was the original price?
23. You invested $2,000 at an annual interest rate of 6%, compounded monthly. What is the total amount after two years?
24. A company’s revenue decreased by 15%, and then increased by 10%. What is the overall percentage change in revenue?
25. If a solution is 25% acid, and another solution is 15% acid, what ratio should they be mixed in to create a 20% acid solution?
26. A rectangular box has dimensions of 8 cm by 12 cm by 16 cm. What percentage of the box’s volume is the space inside?
27. You scored 70 out of 100 on a test. What is the minimum percentage you should score on the next test to have an average of 75%?
28. A company’s profits decreased by 10% and then increased by 15%. What is the overall percentage change in profits?
29. If a product’s price is increased by 5%, and then decreased by $10, the result is the original price. What was the original price?
30. The attendance at an event was 5,000, and it increased by 25% the following year. What is the new attendance?
31. The company’s expenses are $120,000, representing 30% of the revenue. What is the total revenue?
32. If a solution is 40% alcohol, and another solution is 20% alcohol, what ratio should they be mixed in to create a 30% alcohol solution?
33. The price of a watch increased by 20% and then decreased by 10%. What is the net percentage change?
34. You received a 15% discount on a $300 laptop, and then you received an additional 5% off with a coupon. What is the final price?
35. If 15% of a number is 45, and 30% of the same number is 90, what is the number?
36. A company’s revenue is $300,000, and the profit is $60,000. What is the profit margin as a percentage?
37. The price of a phone decreased by 25% and then increased by $30. If the final price is $180, what was the original price?
38. If a rectangle has a length of 8 cm and a width of 10 cm, and both dimensions are decreased by 15%, what is the new area?
39. A company’s profits are $120,000, representing 25% of the revenue. What is the total revenue?
40. The price of a laptop is at a 15% discount. If the original price is unknown, what is the maximum percentage by which the price could be?
41. The company’s expenses are $90,000, representing 15% of the revenue. What is the total revenue?
42. You borrowed $10,000 at an annual interest rate of 10%. How much interest will you owe after two years?
43. The value of a car depreciated by 8% in the first year, and then appreciated by 5% in the second year. What is the net percentage change?
44. If a store offers a 25% discount on a $180 watch and then charges 8% sales tax, what is the final price?
45. A company’s stock price increased by 15% then decreased by $20. If the final price is $140, what was the original price?
46. The price of a dress increased by 10% and then decreased by $15. If the final price is $135, what was the original price?
47. If a solution is 30% sugar, and another solution is 40% sugar, what ratio should they be mixed in to create a 35% sugar solution?
48. The company’s market share decreased by 15% and then increased by 10%. What is the net percentage change?
49. You sold a product for $80, and the selling price was a 40% loss. What was the cost price?
50. The price of a TV is a 20% discount. If the original price is unknown, what is the minimum percentage by which the price could be?