# Examples for 9th grade - page 106

1. Intersections Find the intersections of the function plot with coordinate axes: f (x): y = x + 3/5
2. Rectangle area The length of a rectangle of x units is increased by 10% and its width of y units is increased by 15%. What is the ratio of the area of the old rectangle to the area if the new rectangle?
3. A jackpot How many times must I play this jackpot to win? A jackpot of seven games having (1 X 2), i. E. , home win or away win.
4. Carla Carla is 5 years old and Jim is 13 years younger than Peter. One year ago, Peter’s age was twice the sum of Carla’s and Jim’s age. Find the present age of each one of them.
5. Two equations Solve equations (use adding and subtracting of linear equations): -4x+11y=5 6x-11y=-5
6. Mixture 2 How many liters of water must be added to 7 liters of a 20% solution to obtain a 10% solution?
7. A large A large gear will be used to turn a smaller gear. The large gear will make 75 revolutions per minute. The smaller gear must make 384 revolutions per minute. Find the smallest number of teeth each gear could have. [Hint: Use either GCF or LCM. ]
8. Imagine Imagine that a unit of air at a temperature of 25°C rises up a mountain range that is 3,000 meters high on the windward side and which descends to 1,200 meters on the leeward side, assuming that the air will remain dry what will its temperature when it cro Alaska is the largest state in the United States and has a surface area of approximately 588,000 square miles. Montana has a surface area that is approximately 25% of the surface area of Alaska. What is the approximate surface area of Montana?
10. The volume 2 The volume of a cube is 27 cubic meters. Find the height of the cube.
11. Rocket start The body launched vertically up returns to the start site in 6 seconds. What height did it have?
12. Sand castle Tim and Tom built a sand castle and embellished it with a flag. Half the pole with the flag plunged into the castle. The highest point of the pole was 80 cm above the ground, its lowest point 20 cm above the ground. How high was the sand castle?
13. Rectangular trapezoid In a rectangular trapezoid ABCD with right angles at vertices A and D with sides a = 12cm, b = 13cm, c = 7cm. Find the angles beta and gamma and height v.
14. 15 teachers 15 teachers teach for a combined amount of 128 days over a period of 64 days. What is this expressed as a percentage?
15. Mba studium At MBA school, fourth-year students can choose from three optional subjects: a) mathematical methods, b) social interaction, c) management Each student studies one of these subjects. The mathematical methods studied 28 students, the social interaction 27.
16. Algebra X+y=5, find xy (find the product of x and y if x+y = 5)
17. Price inflation This year the average wage grew by 4.5%. Prices rose by 2%. How much did the real wage increase in the given year?
18. Legs Cancer has 5 pairs of legs. The insect has 6 legs. 60 animals have a total of 500 legs. How much more are cancers than insects?
19. Divide Divide area of rectangles with dimensions 32m and 10m by the ratio 7: 9. What area corresponds to a smaller section?
20. Three tributaries It is possible to fill the pool with three tributaries. The first would take 12 hours, the second 15 hours, and the third 20 hours. The day before the summer season began, the manager opened all three tributaries simultaneously. How long did it take to fil

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