Themes, topics - math word problems
- Water current
John swims upstream. After a while, he passes the bottle, from that moment he floats for 20 minutes in the same direction. He then turns around and swims back, and from the first meeting with the bottle, he sails 2 kilometers before he reaches the bottle.
- Sick days
In Canada, there are typically 261 working days per year. If there is a 4.9% chance that an employee takes a sick day. .. what is the probability an employee will use 17 OR MORE sick days in a year?
- Skid friction
Find the smallest coefficient of skid friction between the car tires and the road so that the car can drive at a 200 m radius at 108 km/h and does not skid.
- The bridge
A vehicle weighing 5,800 kg passes 41 km/h on an arched bridge with a radius of curvature of 62 m. What force is pushing the car onto the bridge as it passes through the center? What is the maximum speed it can cross over the center of the bridge so that
- Same force
The trunk of 5m length and 95 kilograms has a center of gravity 2m from the thicker end. The tribe is carried by two men, one at the thicker end. At what distance does the trunk carry a man from the other end to make the same force on it?
- Angled cyclist turn
The cyclist passes through a curve with a radius of 20 m at 25 km/h. How much angle does it have to bend from the vertical inward to the turn?
- Rotaty motion
What is the minimum speed and frequency that we need to rotate with water can in a vertical plane along a circle with a radius of 70 cm to prevent water from spilling?
The driver loosened the nut on the car wheel with a wrench that held 20 cm from the axis of the bolt. He acted on the key with a force of 320N. At what moment did he act on the bolt?
- Two trains
Two trains departed from City A and City B against each other. They met after some time. The first train then took 9 hours to reach city B, and the second train took 4 hours to reach city A. In what proportion were the train speeds?
- A cold front
At 1:00 PM, the temperature was at 46 degrees. Then, a cold front moved in and decreased the temperature 12 degrees per hour. The temperature at 6:00 PM = _____ degrees.
- Baking muffins
Aunt Polly is baking muffins at a speed of 4 muffins per minute. Tom comes into the kitchen when Aunt Polly has 12 muffins, and begins to eat these muffins at a speed of 6 muffins per minute. When he finally leaves the kitchen, there are 4 muffins at the
- Panel house
The construction company has two groups of workers. Group A has more members than B. Panel house was insulated by group A in 10 days. The same block of flats was insulated together in 6 days. How many days would group B block insulate?
- Temporary workers
Three temporary workers work in the warehouse and unload the goods in 9 hours. In what time would five temporary workers unload the same products?
The pool can be filled with two different tributaries. The first inflow would fill the pool in 18 hours, both in 6 hours. How many hours would the pool filled with a second inflow?
- Two machines
The first machine can produce parts in 24 hours, the second in 16 hours. The first started working in the morning at 6:00 pm. Second at 10:00 o'clock. At what hour were all parts made?
- Pouring alcohol
100 liters of alcohol has 70% How many liters of water need to be added to have 60% alcohol?
- Cheetah vs antelope
When the cheetah began chasing the antelope, the distance between them was 120 meters. Although the antelope was running at 72km/h, the cheetah caught up with it in 12 seconds. What speed was the cheetah running?
- Two companies
The family ordered two companies to modify the garden. The first would be done in 20 days, the second would take 40% less time. How long will they work together if the second company started working when the first worked for 4 days?
- Fruit salad
The fruit salad is prepared from oranges and bananas. One kilogram of oranges costs 30 CZK and one kilogram of bananas costs 18 CZK. How many kilograms of bananas need to be added to half a kilogram of oranges to produce a fruit salad worth CZK 21 per 1 k
- Two ships
Two ships sailed from Venice - a cargo speed of 10 knots and a ferry speed of 18 knots. At what time will the ferry catch up with the cargo ship if it sailed 10 hours later?