Math topic中文

Increase decrease

increasing/decreasing a quantity by a given percentage

Practice questions

  1. 1Mrs Ang runs a small tuition centre for secondary school students. The tables provide information on the cost of running…
  2. 2某商品提价25%后，欲恢复原价，则应降价（ ） A. 40% B. 25% C. 20% D. 15%
  3. 3某楼盘去年每平方米售价50005000元，今年均价上涨了20％20％，房产公司为促销推出以下优惠方案。 方案一：20002000元办一张贵宾卡，可享受九八折优惠。 方案二：不打折，每平方米送8080元装修费。 (1)李叔叔家准备买一套…
  4. 4Hamid borrowed a sum of money for 3 years at an interest rate of 3.5% per annum simple interest to pay for his car. If t…
  5. 5y is inversely proportional to the square of x, x>0x > 0. If x is increased by 25%, find the percentage change in y. Answ…
  6. 6The marked price of a mobile phone is $1288. After selling the mobile phone at 15% discount, the shop owner still makes…
  7. 7Sam is a 40-year-old man who earns a gross salary of $8000 a month. He is a Singaporean and an employee of a Singapore…
  8. 8Elva invested a sum of money in an account paying compound interest at 4% per year. After 3 years, there was $89 989.12…
  9. 9Mr Robert stay in a semi-detached house and is concerned about the rising electricity costs. After reading about solar p…
  10. 10一件服装标价500元，若以6折销售，仍可获利20%，则这件服装进价为 元．
  11. 11The following stem-and-leaf diagram shows the marks obtained by 20 pupils in a class test that has a total mark of 50. S…
  12. 12The force, F units, between two objects is inversely proportional to the square of the distance, d units, between them.…
  13. 13一块地前年产小麦30t30t，去年因水灾减产二成，今年又增产二成，今年产量和前年相比()(\quad) A. 增加了 B. 减少了 C. 不变
  14. 14Mrs Boey deposited $20 000 in a bank that pays 0.8% per annum compound interest compounded half-yearly. Find the total…
  15. 15The cost of manufacturing a sofa is S$1500. It is sold to a retailer at a profit of 15% of the cost. Calculate the pric…
  16. 16一辆中巴从白马井驶往三亚，每小时行60千米，要4小时才能到达．如果速度提高25%，多少小时才能到达？
  17. 17一种杂志，批发商按定价的七折批发给书摊，摊主将定价减少一成卖给读者，如果这种书每本卖6.3元，每本杂志的批发价是多少元？
  18. 18某同学在AA，BB两家超市发现他看中的随身听的单价相同，书包单价也相同.随身听和书包单价之和是452452元，且随身听的单价比书包单价的44倍少88元． (1)求该同学看中的随身听和书包的单价各是多少元？ (2)某…
  19. 19The air resistance, RR newtons, is directly proportional to the square of the speed, VV m/s, of an object when it is f…
  20. 20Mrs Boey deposited $20000\char36{}20 000 in a bank that pays 0.8% per annum compound interest compounded half-yearly. Find the tota…
  21. 21On 6 June 2020, Elijah invested some money in a bank which pays a simple interest at a rate of 3.5% per annum. He receiv…
  22. 22John owns a cleaning company that cleans office blocks. The number of employees in his company and their salaries in 202…
  23. 23The table below shows part of Ahmad's personal income tax bill. Calculate the values of p and q. Answer p = ... q = ...…
  24. 24王老师把2000元存入银行，定期三年，年利率为3.24%，到期后可取回本金和税后利息共多少元？（利息税率20%）
  25. 25Mr Smith plans to invest his money in unit trust with a bank. His target is to earn an interest of $10,000 after 5 year…
  26. 26A company sells chocolate muffins and banana muffins. These muffins are sold across three different outlets, which are O…
  27. 27The table shows the currency exchange rate between Singapore dollars ($) and Thai Baht (THB) at a money changer. Before…
  28. 28The table below shows the price board displayed at a petrol station on 12 April 2023. Pump price refers to the price bef…
  29. 29PP is inversely proportional to Q3Q^3. Find the percentage change in PP when QQ is reduced by 20%. Answer ...%
  30. 30A coffee vendor sells three types of coffee beverages: Latte, Cappuccino and Mocha. The cups of coffee come in three dif…
  31. 31Javelle went to a café and ordered a slice of cake and a cup of tea. Unfortunately, the receipt was stained and parts of…
  32. 32y is proportional to xnx^n. x and y are the length and breadth of a rectangle with a fixed area. State the value of n. F…
  33. 33The cash price of a washing machine is $840. If paid by hire purchase scheme, the deposit is 15% of the cash price and…
  34. 34Joe is interested to buy a new car. He has shortlisted 2 cars, which he intends to drive for 10 years. The following tab…
  35. 35Mr Lee and his wife are going for a family trip to Thailand. The table shows the travel insurance premiums payable for i…
  36. 36某村前年产苹果30万千克，去年增产20%，今年减产20%，今年产量为（ ） A. 29 万千克 B. 31 万千克 C. 28.8 万千克 D. 29.2 万千克
  37. 37打九折出售，就是按原价的 ％出售，比原价便宜了 ％
  38. 38As of 2023, the population of Singapore is approximately 5.64 million and the population of Malaysia is approximately 33…
  39. 39In stall A, one Chicken pie costs 1.50,oneMushroompiecosts1.50, one Mushroom pie costs 1.30 and one Tuna pie costs 1.80.InstallB,oneChickenpiecosts1.80. In stall B, one Chicken pie costs …
  40. 40On the map, 3 MRT stations, Braddell (NS18), Caldecott (CC17) and Toa Payoh (NS19) are joined to form a triangle. constr…
  41. 41（1）医院医改取消药品加价15%，医院管理控制医生乱开药，制定了每个临床科室的药品占整个医疗收入的比例，内科系统医改前的药占比为39.5%，那么医改后应为多少？ （2）这次医改相应提高了医疗价格用于弥补药品取消加价减少的收入，弥补的幅度为药…
  42. 42Hand sanitisers, hand wash and wipes were sold in two pharmacies. The matrix P shows the number of items available for s…
  43. 43A sheet of rectangular paper has length ll cm and breadth bb cm. If identical squares of side 3 cm are to be cut out f…
  44. 44y is directly proportional to x3\sqrt[3]{x}. Find the percentage increase of y when x increases by 700%. Answer ... % 6…
  45. 45一本课外书，原价30元，现在书按八五折出售，书比原价便宜了 元．
  46. 46u is inversely proportional to the square of t. Sketch the graph of u=2t2u = \dfrac{2}{t^2}. Answer: Find the percentage ch…
  47. 47超市运来黄瓜300300千克，比运来的西红柿少25％25％，运来西红柿多少千克？
  48. 48王奶奶买鸡蛋，第二周比第一周涨价5％5％，第三周比第二周涨价3％3％，第二周和第三周一共涨价百分之几??
  49. 49y is inversely proportional to the square root of x. It is given that y=5y=5 for a certain value of xx. Find the value o…
  50. 50Rebecca always travels by taxi to work. To get a taxi, she has two options. She can either flag down a taxi at the roads…
  51. 51If the length of a rectangle is increased by 20% and its width is decreased by 20%, explain whether there is any change…
  52. 52Naomi received a commission of $35 750 from the sale of a house. This sum of money was divided among his expenditure, i…
  53. 53xx and yy are related such that xx is inversely proportional to the square of yy. If yy is increased by 400%, find…
  54. 54A baking school offers beginner, intermediate and advanced baking classes on weekdays and weekends in August this year.…
  55. 55妈妈将5000元人民币存入银行定期1年，年利率为2.52%，利息税为5%，到期后，妈妈可从银行取回本金和利息共多少元？
  56. 56大学生小刘正在出售一批衬衫，每件提价25％25％后发现销路不是很好，欲恢复原价，则每件衬衫应降价()(\quad) A. 15％15％ B. 20％20％ C. 25％25％ D. 30％30％
  57. 57某件商品原售价是50元，因销售不好打九折出售，后又因商品紧俏提价若干，每件商品售价为54元，问提价的百分率是多少？
  58. 58某商家将一种商品按进价提高25％25％后定价，然后打出“九折酬宾，结果每件商品获利208208元． (1)求每件商品的进价； (2)另有一家商家出售同类产品，按进价提高40％40％，然后打出“八折酬宾”的广告，如果你想买这种产品，应选…
  59. 59The cash price of a gaming device is $710. Jolene buys this gaming device on hire purchase and pays a 30% deposit. The…
  60. 60“实际产量是计划的115%，是 与 相比较，实际比计划增产 %．