Maths practice for 14 year olds - page 316 of 321
Number of problems found: 6406
- Pipes
The water pipe has a cross-section 1184 cm². An hour has passed 743 m³ of water. How much water flows through the pipe with cross-section 300 cm² per 6 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 - The angle of lines
Calculate the angle of two lines y=2x+29 and y=-3x+1 - Median
In the right triangle are sides a=96 dm b=31 dm. Calculate the length of the medians tc to the hypotenuse. - Secret number
Find the secret number n, which reversed decreases by 16.4 if the number increases by 16.4.
- 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 74°. They will join with a circular arc with a radius r=1127 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 44 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. - Heron backlaw
Calculate the unknown side in a triangle with sides 24 and 40 and area 299.6.
- 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 = 490 cm² and one diagonal u2 = 39 cm. - Cone and cube
About what percentage has cone with base radius r larger volume than a same high cube with square base with edge length r? - Cable car
The cable car rises at an angle of 44° and connects the upper and lower station with an altitude difference of 1089 m. How long is an "endless" tow rope? - Trigonometry
If you know that cos(γ) = sin (806°), what is the angle γ?
Chord MN of the circle has distance from the center circle S 120 cm. Angle MSN is 64°. Determine the radius of the circle.Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
