Reason + comparing - practice problems
Number of problems found: 22
- Gas prices 2021
According to the SPP price list in 2021, the price of natural gas together with its supply is as follows: D1 - we cook. Fix 3.34 euros/month and 0.0479 euros/kWh (1 cubic meter of gas is approximately 10.555 kWh. It is called combustion heat and changes o
- Chi square
A manufacturer of phone batteries claims that his batteries' lives are approximately normally distributed with a standard deviation equal to 0.9 years. If a random sample of 10 of these batteries has a standard deviation of 1.2 years. Do you think that th
From a box of spruce seeds with the germination of 80%, we randomly select 10 seeds and plant them. Find the median of the random variable: the number of germinating seeds.
- Used cars
Peter plans to buy a used car: the first car Renault Espace 2.0 dCi 16V Dynamique 2006, costs 2000 euros. It is 14 years old and has a combined diesel consumption of 8 liters. / 100 km. Diesel costs 1.1 euros/liter. How much will the car cost him to opera
- How many
How many numbers are less than 222 with a digit sum is 8?
- School year
At the beginning of the school year, 396 notebooks and 252 textbooks are ready to be distributed in the classroom. All pupils receive the same number of notebooks and the same amount of textbooks. How many pupils are there in the class if you know that th
- Positive integers
Several positive integers are written on the paper. Michaella only remembered that each number was half the sum of all the other numbers. How many numbers could be written on paper?
- 600 pencils
600 pencils we want to be divided into three groups. The biggest groups have ten pens more than the smallest. How many ways can this be done?
- The Hotel
The Holiday Hotel has the same number of rooms on each floor. Rooms are numbered with natural numerals sequentially from the first floor, no number is omitted, and each room has a different number. Three tourists arrived at the hotel. The first one was in
Seven classmates go every day for lunch. If they always come to the front in a different order, will be enough school year to take of all the possibilities?
Ivo wants to draw all the triangles whose two sides of which have a length of 4 cm and 9 cm, and the length of the third side is expressed in whole centimeters. How many triangles does he have?
- Sum on dice
We have two dice. What is the greater likelihood of fall a total sum 7 or 8 ? (write 7, 8 or 0 if the probabilities are the same)?
- The door
The door to the apartment has a height 2 m and a width 80 cm. Calculate how many cm of sealing tape is needed to seal them. Will there be enough packaging in which there are 5 m tape (write 0 = no, 1 = yes)?
- Nine balls
Imagine that you have exactly the same appearance nine balls of which one has a greater mass than the other. You have isosceles weights. Post a procedure as you would using a weights to discover heavier balls. How many measurements at least you have to do
Television is the fifth most expensive and tenth cheapest TV. How many different TVs are in stores?
On the meadow grazing horses, cows, and sheep, together with less than 200. If cows were 45 times more, horses 60 times more, and sheep 35 times more than there are now, their numbers would equally. How many horses, cows, and sheep are on the meadow toget
The school stands 110 m from the church, which is 100 m beyond the town hall. Which building are closer to the church and how many times?
- More money
Lenka has €4.8 more than Natalia. Who will have more and how much, when Lenka give Natalia €2.5?
Head of logistics department informed the meeting of management of the same item is currently not available in sufficient quantity in all three warehouses of the company. We have the total 135 pieces. It was 37 pieces more in the warehouse No. 3 than in t
The root of the equation (x-19)² -10 = x² -11x is (equal or greater or less than zero)? ...
Reason - practice problems. Comparing - practice problems.