Time - high school - math problems
Number of problems found: 217
- Common ratio
If 200 units of a commodity are consumed in a first year, and if the annual rate of increase in consumption is 5% (a) what amount is consumed in the 8th year; (b) in the first 15 years?
- When I
When I am as old as my older brother is today, my brother will be twice as old as I am today. a) How old is my brother if I am 8 years old today? b) How old am I if my brother is 21 today?
- The ages
The ages of the four sons make an arithmetic sequence, the sum of which is the age of the father today. In three years, the father's age will be the sum of the ages of the three eldest sons, and in the next two years and three months, the father's age wil
- 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.
- Harmonic oscillator
Calculate the total energy of a body performing a harmonic oscillating motion if its mass is 200 g, the amplitude of the deflection is 2 cm and the frequency is 5 Hz. Round the result to 3 decimal places.
- 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?
- Concrete column
The concrete column of the highway bridge has the shape of a block with dimensions of 1m x 0.8m x 25m. It should be lifted by crane to a height of 20m. What is the power of his engine if the lifting takes 2 minutes?
- This year
This year 2020 is a leap year. How many leap years there had been be since 1904?
- 2 cyclists and car
One cyclist rides at a constant speed over a bridge. It is 100 meters long. When he is 40 meters behind him, he meets an oncoming cyclist who is riding at the same speed. The car travels along the bridge in the same direction as the first cyclist at a spe
- Deceleration of car
The car has a speed of 60 km/h and after 100 m journey speed of 40 km/h. What is the deceleration of a car if we assume that its movement is constantly slowed down?
Suppose on your 21st birthday you begin making monthly payments of $500 into an account that pays 8% compounded monthly. If you continue the payments untill your 51st birthday (30 years), How much money will be in your account? How much of it is interest?
- Double-track line
A 160 m long passenger train runs on a double-track line in one direction at a constant speed of 54 km/h, and a 240 m long express train in the opposite direction. a) How fast is the express train if passing the passenger train driver for 6 s? b) How long
- The half life
The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 145 grams of a radioactive isotope, how much will be left after 3 half-lives?
- Journey to spa
Mr. Dvorak took his wife to the spa and the journey took 3.5 hours. On the way back, he drove 12 km/h faster and was home in 3 hours. At what speed did he go to the spa and at what speed did he return?
- Corona virus
Calculate an estimate of the percentage of GDP (Gross Domestic Product) declined due to the quarantine related to the corona COVID-19 virus that lasts for 2 months, during which time the economic activity is down by 80%.
- Working together
Two people will do the work in 12 days. They worked together for 8 days. Then only one worked for 10 days. How many days would each of them do the work if he worked alone?
- Birthday paradox
How large must the group of people be so that the probability that two people have a birthday on the same day of the year is greater than 90%?
- Maxwell’s inductance bridge
The four arms of Maxwell’s inductance bridge are; Arm AB contains an Inductive coil of inductance L1 having resistance R1. Arms BC and CD contain non-inductive resistances of 200Ω and 100Ω respectively. Arm AD contains standard inductor of inductance L2 a
- Self-oscillation period
The water in the vessel carried by the boy has a self-oscillation period of 0.8 s. What is the size of the boy's movement speed when the length of the boy's step is 60 cm? Give the result in m/s.
The depositor regularly wants to invest the same amount of money in the financial institution at the beginning of the year and wants to save 10,000 euros at the end of the tenth year. What amount should he deposit if the annual interest rate for the annua
Do you want to convert time units like minutes to seconds?