# 9th grade (14y) + direct relationship - examples

- Trapezoid - intersection of diagonals

In the ABCD trapezoid is AB = 8 cm long, trapezium height 6 cm, and distance of diagonals intersection from AB is 4 cm. Calculate trapezoid area. - Sick

Six seamstresses should make 60 shirts in five business days. After three days two seamstresses were sick. How many days have the remaining seamstresses to finish contract? - Pool

If water flows into the pool by two inlets, fill the whole for 12 hours. First inlet filled pool 6 hour longer than second. How long pool is filled with two inlets separately? - Bonus

Gross wage was 1762 USD including 22% bonus. How many USD were bonuses? - Beer

After three 10° beers consumed in a short time there are 5.2 g of alcohol in 6 kg adult human blood. How much is it per mille? - Server

Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%. - Gimli Glider

Aircraft Boeing 767 lose both engines at 45000 feet. The plane captain maintain optimum gliding conditions. Every minute, lose 2080 feet and maintain constant speed 196 knots. Calculate how long takes to plane from engines failure to hit ground. Calculate - Scale

Swimming pool is long 110 m and 30 m wide. The plan of the city is shown as a rectangle with area 13200 cm^{2.}What scale is the city plan? - Pipes

Water pipe has a cross-section 1420 cm^{2.}An hour has passed 831 m^{3}of water. How much water flows through the pipe with cross-section 300 cm^{2}per 8 hours if water flow same speed? - Cyclist

Cyclist goes uphill 1 km for 6.3 minutes and downhill minutes for 2.1 minutes, both applied to the pedals same force. How long he pass 1 km by plane? - Engineer Kažimír

The difference between politicians-demagogues and reasonable person with at least primary education beautifully illustrated by the TV show example. "Engineer" Kažimír says that during their tenure there was a large decline in the price of natural gas, pri - Road repair

Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day? - Gear

Two gears, fit into each other, has transfer 1:5. Centres of gears are spaced 28 cm. What are the radii of the gears? - Radians

Convert 54° to radians. Write result as multiple of number π. - Pediatrician

Pediatrician this month of 21 working days takes 3 days holidays. What is the probability that on Monday will be at work? - Train and car

The train and the car started at a constant speed to journey. When the train travels 78 km, the car travels 64 km. How many km travels the train when the car travels 78 km? - Negative percentage

In 2003, the company had a loss of 25600 Euros. Two years later he was already in profit 25200 Eur. Calculate what percentage of the company increased profits in this two years. - Saving

Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car? - Pizza

Pizza with a diameter 41 cm have weight 531 g. What diameter will have a pizza weighing 749 g if it is make from the same cloth (same thickness....) and same decorated? - ISO triangle

Calculate the area of an isosceles triangle KLM if the length of its sides are in the ratio k:l:m = 4:4:3 and has perimeter 128 mm.

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