# Examples for 9th grade - page 107

1. Divide Divide area of rectangles with dimensions 32m and 10m by the ratio 7: 9. What area corresponds to a smaller section?
2. 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
3. Diofant equation 250x + 120y = 5640
4. A triangle A triangle has an angle that is 63.1 other 2 are in ratio of 2:5 What are the measurements of the two angles?
5. Two unknown numbers One number is 2 less than a second number. Twice the second number is 14 less than 5 times the first. Find the two numbers.
6. Midpoint 4 If the midpoint of a segment is (6,3) and the other end point is (8,-4) what are thw coordinate of the other end?
7. Combinations 7 A multi-course meal has 3 choices. 3 appetizers, 4 main courses, and 3 desserts. How many different combinations to choose from?
8. Blocks There are 9 interactive basic building blocks of an organization. How many two-blocks combinations are there?
9. Linear system Solve a set of two equations of two unknowns: 1.5x+1.2y=0.6 0.8x-0.2y=2
10. Expression with powers If x-1/x=5, find the value of x4+1/x4
11. Journey 5 A man has to do a journey of 84km in 3 hours. He travels the first 30km at 20km/hr. At what rate must he travel the remaining distance to complete his journey on time? Montealegre family has a catering business. In one birthday party, they charged their costumer 11,767.50 for a party of 90 persons and a service charge of 2,500.50. How much was the average cost per person? Please show your solution.
13. 5 people 5 people have \$122000 and 1 person has \$539000 How much should each person (equally) pay?
14. Value 4 If 5/18=425 what is the value 13/18?
15. Rectangular field A rectangular field has a diagonal of length 169m. If the length and width are in the ratio 12:5. Find the dimensions of the field, the perimeter of the field and the area of the field.
16. Pile of sand A large pile of sand has been dumped into a conical pile in a warehouse. The slant height of the pile is 20 feet. The diameter of the base of the sand pile is 31 feet. Find the volume of the pile of sand.
17. Earth's circumference Calculate the Earth's circumference of the parallel 48 degrees and 10 minutes.
18. Percentage 10 52 shorts and missed 13. Calculate percentage
19. Brakes The braking efficiency of a passenger car is required to stop at 12.5 m at an initial speed of 40 km/h. What is the acceleration braking by brakes?
20. Jane plants Jane plants flowers in the garden. If she planted 12 every hour instead of 9 flowers, she would finish with the job an hour earlier. How many flowers does she plant?

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