Units - problems
- Conical area
A right angled triangle has sides a=11 and b=10 in right angle. The hypotenuse is c. If the triangle rotates on the c side as axis, find the volume and surface area of conical area created by this rotation.
- Thunder and lightning
There was a glimpse of the sky and we hear a thunder in 4.5 seconds. The light spreads at 300,000 kilometers per second, so we can assume the flash instantly without delay. However, the speed of the sound is much smaller in the air one third of a kilomete
- Brick weight
Half the weight of a brick plus 20 pounds is equal to 1/3 the weight of the brick plus 30 pounds. How much does the brick weigh?
- Quadrangular pyramid
Calculate the surface area and volume of a regular quadrangular pyramid: sides of bases (bottom, top): a1 = 18 cm, a2 = 6cm angle α = 60 ° (Angle α is the angle between the side wall and the plane of the base.) S =? , V =?
- Bed time
Tiffany was 5 years old; her week night bedtime grew by ¼ hour each year. If, at age 18, her curfew time is 11pm, what was her bed time when she was 5 years old?
- Hour salary
You work for 4 hours on a Saturday and 8 hours on Sunday. You also receive a $50 bonus. You earn $164. How much did you earn per hour?
Lara Pamela spends her salary of 3000 for food, clothing, recreation and savings, which are in the ratio of 48:20:15:37, respectively. How much does he spend for savings?
Susan's age will be after 12 years four times as much as twelve years ago. How old is Susan now?
- Ebay is not free
Be aware of ebay - if you sell something expensive, fee is painful. There are lot of space for classifieds and local exchange away from global ebay. Calculate ebay+paypal fee if you sale 3641 USD laptop. Formula for ebay fee is 0,30 + 10 % of total earning
Friday 13th is in 4 days. What day is today and what day it is?
- Cylinder horizontally
The cylinder with a diameter of 3 m and a height/length of 15 m is laid horizontally. Water is poured into it, reaching a height of 60 cm below the axis of the cylinder. How many hectoliters of water is in the cylinder?
- Wagons and cranes
Several of the same cranes unloaded 96 wagons. If there were 2 more cranes there would be less 8 wagons for each crane. How many cranes were here?
- Three cubes
The body was created by gluing three identical cubes. Its volume is 192 cm3. What is its surface in dm2?
- Rectangle 39
Find the perimeter and area of the rectangular with vertices (-1, 4), (0,4), (0, -1), and (-4, 4)
- Circle simple
Circumference of a circle is 6.28. What is the area of the circle?
- Free fall
How long does the stone fall freely into a depth of 80m? What speed will it hit the bottom of the abyss?
- Mother and daughter
The mother is four times older than her daughter. Five years ago, her daughter was seven times younger than her mother. How many years do they have now?
- Family 8
Father is 38 years old, daughter 12, son 14. How many years will father have as many years as his children together?
- Parallelogram perimeter
The ABC triangle with sides a = 5cm, b = 3cm, c = 40mm has the center of the sides of the K,L,M. How many cm have the KBLM parallelogram perimeter?
- Tailor 5
A tailor uses 13/4m of cloth to stitch a skirt. How many metres of cloth is needed to stitch 16 skirts?