Examples for 9th grade - page 35
- Disinfecting solution
How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
The cylinder surface is 139 dm2, its height is equal to the radius of the base. Calculate height of this cylinder.
- Hiker and cyclist
At 7 PM hiker started at 6 km/h to hike. After 3 hrs. later started on the same trip cyclist at speed of 15 km/h. After an hour of driving a flat tire and take him half hours to correct defect. At what time catch up cyclist with hiker?
Calculate the height of 3 liter pot with shape cylinder with a diameter of 10 cm.
Two fifth-graders teams competing in math competitions - in Mathematical Olympiad and Pytagoriade. Of the 33 students competed in at least one of the contest 22 students. Students who competed only in Pytagoriade was twice more than those who just competed
Jarek bought new trousers, but the trousers were too long. Their length was in the ratio 5: 8 to Jarek height. Mother his trousers cut by 4 cm, thus the original ratio decreased by 4%. Determine Jarek's high.
I have bevel in the ratio 1:6. What is the angle and how do I calculate it?
- Rhombus IV
Calculate the length of the diagonals of the rhombus, whose lengths are in the ratio 1: 2 and a rhombus side is 35 cm.
What is the slope of the line defined by the equation -4x -2y = -7 ?
- Golden ratio
Divide line of length 526 cm into two sections that the ratio of shorter to greater is same as ratio of greater section to whole length of the line.
The length of the rectangle is 8 smaller than three times the width. If we increase the width by 5% of the length and the length is reduced by 14% of the width, the circumference of rectangle will be increased by 30 m. What are the dimensions of the rectan
- Train 2
The train slowed down from 90 km/h to 72 km/h in 5 seconds. How long track travel?
- Trapezoid IV
In a trapezoid ABCD (AB||CD) is |AB| = 15cm |CD| = 7 cm, |AC| = 12 cm, AC is perpendicular to BC. What area has a trapezoid ABCD?
Calculate the approximate weight of the gold Olympics medal, if its diameter is 9 cm and a thickness 6 mm. The density of gold find out in the tables or on the Internet.
The length of the bases trapezium are in ratio 2:1. Length of midline is 17. How long are the bases of a trapezoid?
- Word problem
384 students were on holiday in Hungary. 146 bought pizza, chips 25 pupils, 39 pupils bought soda, butter 15 pupils, 18 pupils fruits, vegetables 29 students. How much pay for all the food, if every meal cost 4.9 euros?
- Digits A, B, C
For the various digits A, B, C is true: the square root of the BC is equal to the A and sum B+C is equal to A. Calculate A + 2B + 3C. (BC is a two-digit number, not a product).
What is the distance (length) the Earth's meridian 27° when the radius of the Earth is 6370 km?
- Freight and passenger car
The truck starts at 8 pm at 30 km/h. Passenger car starts at 8 pm at 40 km/h. Passenger arrives in the destination city 1 hour and 45 min earlier. What is the distance between the city of departure and destination city?
- Pool 2
The first supply by the pool fill for five hours and the second fill for six hours, drain should be drained for 15 hours. For how many hours the pool is full, when we open both inlet now and outlet open two hours later?