# Examples for 9th grade - page 9

- Words

How many 3 letter "words" are possible using 18 letters of the alphabet? a) n - without repetition b) m - with repetition - Triangle ABC

Right triangle ABC with right angle at the C, |BC|=20, |AB|=35. Calculate the height of the triangle h_{AB}to the side AB. - MATES

In MATES (Small Television tipping) from 35 randomly numbers drawn 5 winning numbers. How many possible combinations there is? - Scrap

From 8 products are 2 scrap. What is the probability that the random pick of 2 products have no defective product? - Pipes

Water pipe has a cross-section 1939 cm^{2.}An hour has passed 567 m^{3}of water. How much water flows through the pipe with cross-section 300 cm^{2}per 14 hours if water flow same speed? - Basketball

Peter and Franta threw to the basket. Each had 20 attempts. Peter scored thirteen and twelve Franta. Give them success in percentage. - 3y inflation

Price of the bread rise in the first year by 7%, the second year fell by 4% and in the third year increased by 8%. Calculate the average annual increase in price of the bread. - Two typists

There are two typists who are rewriting the material 705 pages. First can it handle rewrite yourself for 24 days; the second 12 days. First typist wrote material yourself 4 days rest rewrites yourself second typist. How many days will it take rewriting alt - Subsets

How many is subsets of set ?? - Machine

Price of the new machine is € 56000. Every year is depreciated 16% of residual value. What will be the value of the machine after 5 years? - Three digits number

How many are three-digit integers such that in they no digit repeats? - Lines

In how many points will intersect 11 different lines, where no two are parallel? - Dice

How many times must throw the dice, the probability of throwing at least one three was greater than 90%? - Lock

Combination lock will open when the right choice of 5 numbers (from 1 to 12 inclusive) is selected. A. How many different lock combinations are possible? B. Is he combination lock named appropriately? - Barrel of oil

Barrel of oil weighs 282 kg. When it mold 56% oil, weighed 138 kg. What is the mass of the empty barrel? - Divisors

The sum of all divisors unknown odd number is 1482. Determine sum of all divisors of number which is twice of unknown numbers. - Welders

Welder do the job for six hours, the second one for 8 hours. How long do the job third welder if all together can do job in 2 hours? - Root

Use law of square roots roots: ? - Morse alphabet

Calculate how many words of Morse code to create compiling commas and dots in the words of one to five characters. - Combinations

How many different combinations of two-digit number divisible by 4 arises from the digits 3, 5 and 7?

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