Examples for secondary school students - page 21 of 230
Number of problems found: 4593
- Grouping - combinatorics  In how many different ways can 24 people be divided into: a) 6 groups of the same size. b) Groups of 5, 6, 7, and 6 people. c) Groups of 4, 5, 7, and 8 people. In how many different ways can 24 people be divided into: a) 6 groups of the same size. b) Groups of 5, 6, 7, and 6 people. c) Groups of 4, 5, 7, and 8 people.
- Probability - coin  When tossing a coin 4 times in a row, what is the probability that a sign will come up 3 times? When tossing a coin 4 times in a row, what is the probability that a sign will come up 3 times?
- Heptagon perimeter  Calculate a regular heptagon's perimeter if its shortest diagonal length is u=14.5cm. Calculate a regular heptagon's perimeter if its shortest diagonal length is u=14.5cm.
- The Celebration  Five boys and five girls were nominated for a celebration at a local school. How many ways can the prom king, prom queen, and two other students be chosen from those nominated? (The king must be a boy, and the queen must be a girl) Five boys and five girls were nominated for a celebration at a local school. How many ways can the prom king, prom queen, and two other students be chosen from those nominated? (The king must be a boy, and the queen must be a girl)
- Harvest 83600  Martin brought twice as much harvest as Tomáš and Filip, 15 kg more than Martin. They got a total of 65 kg of harvest. How much did each person bring? Martin brought twice as much harvest as Tomáš and Filip, 15 kg more than Martin. They got a total of 65 kg of harvest. How much did each person bring?
- Intersection + tangents  Given a circle with a radius r = 4 cm and a point A for which |AS| applies = 10 cm. Calculate the distance of point A from the intersection of the points of contact of the tangents drawn from point A to the circle. Given a circle with a radius r = 4 cm and a point A for which |AS| applies = 10 cm. Calculate the distance of point A from the intersection of the points of contact of the tangents drawn from point A to the circle.
- Transformation of voltage  A current of 0.5 A flows through the transformer's primary coil connected to a voltage of 120 V. Calculate the voltage and current in the secondary coil if the transformation ratio is equal to the number 5. A current of 0.5 A flows through the transformer's primary coil connected to a voltage of 120 V. Calculate the voltage and current in the secondary coil if the transformation ratio is equal to the number 5.
- Bulb lifespan  The probability that the bulb will burn for more than 800 hours is 0.2. There are 3 light bulbs in the hallway. What is the probability that after 800 hours, at least one will be lit? The probability that the bulb will burn for more than 800 hours is 0.2. There are 3 light bulbs in the hallway. What is the probability that after 800 hours, at least one will be lit?
- Granulate 83503  Bathing water should have a pH value in the range of 6.8 - 7.2. How much granulate should we add to increase the pH value from 6.2 to 7 if a dose of 100g/10m³ increases the pH by approx. 0.1? P.S. It's not 800 grams. Bathing water should have a pH value in the range of 6.8 - 7.2. How much granulate should we add to increase the pH value from 6.2 to 7 if a dose of 100g/10m³ increases the pH by approx. 0.1? P.S. It's not 800 grams.
- Soap bubble  A conductive soap bubble with a radius of r=2 cm and charged to a potential of φ= 10000 V will burst into a drop of water with a radius of r1= 0.05 cm. What is the potential φ1 of the drop? A conductive soap bubble with a radius of r=2 cm and charged to a potential of φ= 10000 V will burst into a drop of water with a radius of r1= 0.05 cm. What is the potential φ1 of the drop?
- Acceleration 83493  A body with a mass of 5 kg moves in a vertical downward direction with an acceleration of a= 12 m/s². What force acts on it in addition to its weight? A body with a mass of 5 kg moves in a vertical downward direction with an acceleration of a= 12 m/s². What force acts on it in addition to its weight?
- Temperature 83492  How much heat is needed to turn 1kg of ice at a temperature of -10℃ into steam at a temperature of 100℃? How much heat is needed to turn 1kg of ice at a temperature of -10℃ into steam at a temperature of 100℃?
- Calculate  A bicycle rotates with a frequency of f= 25 Hz. By braking, its rotation can be slowed down evenly and the bicycle stops after a time of t0= 30 s from the start of braking. Calculate the angular acceleration Ԑ and the number of revolutions the bicycle mak A bicycle rotates with a frequency of f= 25 Hz. By braking, its rotation can be slowed down evenly and the bicycle stops after a time of t0= 30 s from the start of braking. Calculate the angular acceleration Ԑ and the number of revolutions the bicycle mak
- Coordinates of line points  I have a point A=[2,1] and a line y+x-5=0. How do I determine the coordinates of point A', which is the image of point A according to the given straight line? I have a point A=[2,1] and a line y+x-5=0. How do I determine the coordinates of point A', which is the image of point A according to the given straight line?
- Numbers 6D  Find out how many natural six-digit numbers exist whose digit sum is four. Find out how many natural six-digit numbers exist whose digit sum is four.
- Lifetime - bell curve  Laser lifetime follows a normal distribution with a mean of 7000 hours and a standard deviation of 600 hours. What is the probability that the laser will fail before 6000 hours? What is the probability that the laser will last at least 7500 hours? Laser lifetime follows a normal distribution with a mean of 7000 hours and a standard deviation of 600 hours. What is the probability that the laser will fail before 6000 hours? What is the probability that the laser will last at least 7500 hours?
- Distance  If Danka increases her walking speed by 1km/h, she will cover a distance greater than 20 km in 4 hours. If she decreases her speed by 1km/h, she will not cover more than 20 km in 5 hours. At what speed did Danka walk? (s=v. t;s- distance, v- speed, t- tim If Danka increases her walking speed by 1km/h, she will cover a distance greater than 20 km in 4 hours. If she decreases her speed by 1km/h, she will not cover more than 20 km in 5 hours. At what speed did Danka walk? (s=v. t;s- distance, v- speed, t- tim
- Circumscribed circle ABC  Triangle ABC, with sides a = 15 cm, b = 17.4 cm, and c = 21.6 cm, is circumscribed by a circle. Calculate the area of the segments determined by the sides of the triangle. Triangle ABC, with sides a = 15 cm, b = 17.4 cm, and c = 21.6 cm, is circumscribed by a circle. Calculate the area of the segments determined by the sides of the triangle.
- Circumscribed triangle  Calculate the radius of the circle of the circumscribed triangle, which has side dimensions of 8, 10, and 14 cm. Calculate the radius of the circle of the circumscribed triangle, which has side dimensions of 8, 10, and 14 cm.
- Playmakers + coach  In a basketball game, two pivots, two wings, and one point guard play. The coach has three pivots, four wing players, and two playmakers available on the bench. How many different five players can a coach send to the board during a game? In a basketball game, two pivots, two wings, and one point guard play. The coach has three pivots, four wing players, and two playmakers available on the bench. How many different five players can a coach send to the board during a game?
Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question. 
 