Maths practice for 14 year olds - page 365 of 370
Number of problems found: 7400
- Pipes
The water pipe has a cross-section 1903 cm². An hour has passed 859 m³ of water. How much water flows through the pipe with cross-section 300 cm² per 11 hours if water flows at the same speed? - Chord
In a circle with a radius r=60 cm is the chord, 4× longer than its distance from the center. What is the length of the chord? - Trigonometry
Is true equality? sin(x +13 π)= sin(x) - Rotating cone II
Calculate the area of the surface of a rotating cone with base radius r=15 cm and height h=13 cm. - Gold wire
From one gram of gold was pulled wire 1.4 km length. What is its diameter if the density of Au is ρ=19.5 g/cm³? - Energy saving
They released three different independent inventions saving 15%, 17%, and 16% energy. Some considered that with the use of these inventions, the total savings would be 15% + 17% + 16% = 48%. Is this true? How much will the percent of energy save all three - Bulbs
In the box are 16 bulbs with power 75 W, 14 bulbs with power 40 W, and 10 with 50 W. Calculate the probability that a randomly selected bulb is: a) 40 W b) 75 W or 40 W - The angle of lines
Calculate the angle of two lines y=x-8 and y=+12 - Median
In the right triangle are sides a=96 dm b=31 dm. Calculate the length of the medians tc to the hypotenuse. - Rectangles
How many rectangles with area 8855 cm² whose sides are natural numbers? - Secret number
Find the secret number n, which reversed decreases by 15.4 if the number increases by 15.4. - Rectangle SS
The perimeter of a rectangle is 154 dm, and its diagonal is 62.36 dm. Find the dimensions of the rectangle. - V-belt
Calculate the length of the belt on pulleys with diameters of 105 mm and 393 mm at shaft distance 697 mm. - Track arc
Two straight tracks are at an angle 126°. They will join with a circular arc with a radius r=1110 m. How long will the arc be connecting these lines (L)? How far is the arc's center point from track crossings (x)? - Seedcake
Seedcake costs 20 cents. How many minimum seedcakes must we buy that we can pay in cash, only whole euros? - Sphere slices
Calculate the volume and surface of a sphere if the radii of a parallel cut r1=32 cm, r2=47 cm, and its distance v=21 cm. - Sphere cuts
At what distance from the center does the sphere intersect with the radius R = 46 plane if the cut area and area of the main sphere circle are in ratio 2/5? - Heron backlaw
Calculate the unknown side in a triangle with sides 39 and 38 and area 438.6. - Triangle
Calculate the triangle's heights ABC if the triangle's sides are a=26, b=81, and c=73. - Diamond
Find the side of the diamond if its area is S = 194 cm² and one diagonal u2 = 44 cm.
Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question.
