# Time + expression of a variable from the formula - math problems

#### Number of problems found: 106

• The projectile
The projectile was fired horizontally from a height of h = 25 meters above the ground at a speed of v0 = 250 m/s. Find the range and flight time of the projectile.
• Up and down motion
We throw the body from a height h = 5 m above the Earth vertically upwards v0 = 10 m/s. How long before we have to let the second body fall freely from the same height to hit the Earth at the same time?
• Demographics
The population grew in the city in 10 years from 30000 to 34000. What is the average annual percentage increase of population?
• Two cyclists
Two cyclists started from crossing in the same time. One goes to the north speed 20 km/h, the second eastward at speed 26 km/h. What will be the direct distance cycling 30 minutes from the start?
• Annual increase
The number of cars produced increased from 45,000 to 47,000 in 3 years. Calculate the average annual increase in cars in%.
• Workers
Two workers will construct the stage at the festival in 54 hours. Organizers need to shorten the assembly time by 42 hours. How many workers must the assembly company send?
• Free fall
How long does the stone fall freely into a depth of 80m? What speed will it hit the bottom of the abyss?
• What is
What is the annual percentage increase in the city when the population has tripled in 20 years?
• Annual growth
The population has grown from 25,000 to 33,600 in 10 years. Calculate what was the average annual population growth in%?
• Bus lines
Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
• Two ships
The distance from A to B is 300km. At 7 am started from A to B a ferry with speed higher by 20 km/h than a ship that leaves at 8 o'clock from B to A. Both met at 10h 24min. Determine how far they will meet from A and when they reach the destination.
• Greg and Bill
Greg is 18 years old. He is 6 less than 4 times Bill's age. How old is Bill?
• Two ports
Between the ports of Mumraj and Zmatek, two ships commute along the same route. They spend negligible time in ports, turn around immediately and continue sailing. At the same time, a blue ship departs from the port of Mumraj, and a green ship departs from
• One and a half chicken
One and a half chicken bears one and a half egg in one and a half day. How many eggs can withstand from 6 chicken in 6 days?
• Direct route
From two different places A and B connected by a direct route, Adam (from city A) and Bohus (from city B) started at a constant speed. As Adam continued to go from A to B, Bohus turned around at the time of their meeting and at the same speed he returned
• Car and cyclist
Cyclist started from town at speed 18 km/h. After 1 hour 30 min started the car from town and caught up with the cyclist in 50 minutes. How fast was a car?
• Acceleration
The car accelerates at rate 0.5m/s2. How long travels 400 meters and what will be its speed?
• Growth of wood
The annual growth of wood in the forest is estimated at 2%. In how many years will make the forest volume double?
• Slow saving in banks
How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
• A clock
A clock was set right at 6:00 AM. If it gains 3 1/2 minutes per hour, what time will it show at 6:00 PM on the same day? Show your solution

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