# Equation - 9th grade (14y) - examples

Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?- Cost reduction

Two MP3 players whose price was equal to originally have been discounted the first by 20%, the second by 35%. After the price reduction was the difference in their prices 750, - CZK. What was the original price of each of the two players? - Two rooms

Woman cleans the room in 30 minutes a man in 90 minutes. How long will take they clean two rooms? - Comparing salaries

Spouses compared salaries. Mrs. Janka found that a 20% higher salary than Mr Jaroslav. Together earned € 1,430. How much they earn each of them? - Rectangle

The rectangle has a perimeter 75 cm. Diagonal length is 32.5 cm. Determine the length of the sides. - Sum of money

On a certain sum of money, invested at the rate of 10% compounded annually, the difference between the interests of the first year and the third year is 315 . Find the sum. - Coach

Average age of 24 players and a coach of one team is 24 years. The average age of players without a coach is 23 years. How old is the coach? - Two sisters

Two sisters together have 54 CDs. 6/8 CDs has younger sister and is equal to 3/5 of CDs older sisters. How many CDs has each of the sisters? - Workers

9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long? - Way

If the current way to school was 2 km shorter then if Milan swipe one half he will have already one quarter of the way to school behind. How long is Milan's way to school? - Triangle ABC v2

Area of the triangle is 12 cm square. Angle ACB = 30º , AC = (x + 2) cm, BC = x cm. Calculate the value of x. - Proof PT

Can you easy prove Pythagoras theorem using Euclidean theorems? If so, do it. - Troops

Route is long 203 km and the first day first regiment went at an average speed 20 km/h and journey back 19 km/h. The second day went second regiment same route at an average speed 18 km/h there and back. Which regiment will take route longer? - Stock market

Simon one day decided to invest € 48000 to the stock market. After six months he invested July 11 stock markets fell by 43%. Fortunately for Simon from July 11 5 to October 11 his shares have risen by 13%. Simon is then: ? - Logic

A man drinks a barrel of water for 31 days, woman for 58 days, for how many days they drink barrel together? - Right Δ

Right triangle has length of one leg 7 cm and length of the hypotenuse 25 cm. Calculate the height of the triangle. - Beer

After three 10° beers consumed in a short time there are 7.4 g of alcohol in 5 kg adult human blood. How much is it per mille? - MO SK/CZ Z9–I–3

John had the ball that rolled into the pool and it swam in the water. Its highest point was 2 cm above the surface. Diameter of circle that marked the water level on the surface of the ball was 8 cm. Determine the diameter of John ball. - Saving

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

Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros? - Vinegar 2

How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar?

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