Examples for secondary school students - page 79

  1. Car repair
    cars John bought a car for a certain sum of money. He spent 10% of the cost to repairs and sold the car for a profit of Rs. 11000. How much did he spend on repairs if he made a profit of 20%?
  2. A fisherman
    worms A fisherman buys carnivores to fish. He could buy either 6 larvae and 4 worms for $ 132 or 4 larvae and 7 worms per $ 127. What is the price of larvae and worms? Argue the answer.
  3. Intersect and conjuction
    venn_intersect Let U={1,2,3,4,5,6} A={1,3,5} B={2,4,6} C={3,6} Find the following. 1. )AUB 2. )A'UB'
  4. Life expectancy
    normal_d The life expectancy of batteries has a normal distribution with a mean of 350 minutes and standard deviation of 10 minutes. What the range in minutes 68% of the batteries will last? What is the range in minutes approximately 99.7% of batteries will last?
  5. Tabitha
    factory_butter_7 Tabitha manufactures a product that sells very well. The capacity of her facility is 241,000 units per year. The fixed costs are $122,000 per year and the variable costs are $11 per unit. The product currently sells for $17. a. What total revenue is requ
  6. The hiker
    tourist The hiker will travel 40% of the route on the first day 1and/3 of the rest od second day. Last day 30 km. What was the length of the 3-day trip? How many kilometers did he walk each day?
  7. Seat
    cubes3 How much m² of fabric do we need to sew a 50cm-shaped cube-shaped seat if 10% of the material we add to the folds?
  8. Gasoline-oil ratio
    fuel-pump The manufacturer of a scooter engine recommends a gasoline-oil fuel mixture ratio of 15 to 1. In a particular garage, we can buy pure gasoline and a gasoline-oil mixture, which is 75% gasoline. How much gasoline and how much of the gasoline-oil mix do we
  9. Graduation party
    dancers There are 15 boys and 12 girls at the graduation party. Determine how many four couples can be selected.
  10. Base of prism
    hranol3b The base of the perpendicular prism is a rectangular triangle whose legs length are at a 3: 4 ratio. The height of the prism is 2cm smaller than the larger base leg. Determine the volume of the prism if its surface is 468 cm2.
  11. Isosceles triangle 9
    iso_triangle Given an isosceles triangle ABC where AB= AC. The perimeter is 64cm and altitude is 24cm. Find the area of the isosceles triangle
  12. Accelerated motion - mechanics
    dodavka The delivery truck with a total weight of 3.6 t accelerates from 76km/h to 130km/h in the 0.286 km long way. How much was the force needed to achieve this acceleration?
  13. Median
    statistics The number of missed hours was recorded in 11 pupils: 5,12,6,8,10,7,5,110,2,5,6. Determine the median.
  14. Prices
    pokladna The price of the product was increased by 35%. How many percents of the new price we have to make it cheaper so that its price is equal to the original price?
  15. Set of coordinates
    axes2 Consider the following ordered pairs that represent a relation. {(–4, –7), (0, 6), (5, –3), (5, 2)} What can be concluded of the domain and range for this relation?
  16. Genetic disease
    flu One genetic disease was tested positive in both parents of one family. It has been known that any child in this family has a 25% risk of inheriting the disease. A family has 3 children. What is the probability of this family having one child who inherited.
  17. GP - three members
    progression_ao The second and third of a geometric progression are 24 and 12(c+1) respectively, given that the sum of the first three terms of progression is 76 determine value of c
  18. Two math problems
    coins 1) The sum of twice a number and -6 is nine more than the opposite of that number. Find the number. 2) A collection of 27 coins, all nickels, and dimes, is worth $2.10. How many of each coin are there? The dime, in United States usage, is a ten-cent coin
  19. Three members GP
    exp_growth The sum of three numbers in GP (geometric progression) is 21 and the sum of their squares is 189. Find the numbers.
  20. An investment
    exp_growth2 How long will it take for an investment to double at a simple interest rate of 5.10% p. A. ? Express the answer in years and months, rounded up to the next month.

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