Themes, topics - math word problems - page 122 of 124
Number of problems found: 2469
- Ten cashiers
Ten cashiers are open at Tesco. Customers wait an average of 15 minutes. How many other cashiers have to open to reduce the waiting time by 4 minutes?
- Inscribed circle
Write the equation of an incircle of the triangle KLM if K [2,1], L [6,4], M [6,1].
- Equilateral cylinder
A sphere is inserted into the rotating equilateral cylinder (touching the bases and the shell). Prove that the cylinder has both a volume and a surface half larger than an inscribed sphere.
- Octahedron - sum
On each wall of a regular octahedron is written one of the numbers 1, 2, 3, 4, 5, 6, 7, and 8, wherein on different sides are different numbers. John makes the sum of the numbers written on three adjacent walls for each wall. Thus got eight sums, which al
The student drew the cylinder in scale 2:1. How many times is the volume of the cylinder smaller in reality?
- Distribution 6283
The life of the bulbs has a normal distribution with a mean value of 2000 hours and a standard deviation of 200 hours. What is the probability that the light bulb will last for at least 2100 hours?
- See harmonics
Is it true that the size of the central segment of any trapezoid is the harmonic mean size of its bases? Prove it. The central segment crosses the intersection of the diagonals and is parallel to the bases.
- Intersect 5216
At how many points do ten lines intersect if no two are parallel?
- Instantaneous 37201
The amplitude of the linear undamped harmonic oscillator is A = 12 cm, and the frequency f = 15 Hz. What is its instantaneous deflection at time a) t1 = 0.02s, b) t2 = 0.04s, when it was zero at time t = 0 s?
- Sphere floating
Will a hollow iron ball float with an outer diameter d1 = 20cm and an inside diameter d2 = 19cm in the water? The iron density is 7.8 g/cm³. (Instructions: Calculate the average sphere density and compare it with the water density. )
- A hiker
A hiker plans to hike up one side of a mountain and down the other side of points a mountain, each side of the mountain formed by a straight line. The angle of elevation at the starting point is 42.4 degrees, and the angle of elevation at the end is 48.3
- 3 phase load
Two wattmeters are connected to measure power in a 3 phase balanced load. Determine the total power and power factor if the two wattmeters read 1000 watts each (1) both positive and (2) the second reading is negative.
- Oscillating 37271
Calculate the oscillation time T of the undamped harmonic oscillating motion of a particle of mass m = 10 g if the force holding the particle in this motion has a value of F = 0,05 N at a deflection of x = 3 cm.
- CuSO4 mixture
How many grams of solid CuSO4 do we have to add to 450g of 15% CuSO4 solution to produce a 25% solution?
- Eight blocks
Dana had the task of saving the eight blocks of these rules: 1. Between two red cubes must be a different color. 2. Between two blue must be two different colors. 3. Between two green must be three different colors. 4. Between two yellow blocks must be fo
- Map - climb
On the map of the High Tatras, on a scale of 1:11000, are cable car stations in the Tatranska Lomnica and the Skalnate Pleso with a distance of 354.6 mm. The altitude of these stations is 949 m and 1760 m. What is the average angle of climb on this cable
- The body
The body slides down an inclined plane, forming an angle α = π / 4 = 45° under the action of a horizontal plane under the effect of friction forces with acceleration a = 2.4 m/s². At what angle β must the plane be inclined so that the body slides on it af
- Oscillation 48961
Write the equation of harmonic oscillation if the amplitude of the oscillation is 5 cm and its period is 0.5 s.
- Centroid - two bodies
A body is composed of a 0.8 m long bar and a sphere with a radius of 0.1m attached so that its center lies on the longitudinal axis of the bar. Both bodies are of the same uniform material. The sphere is twice as heavy as the bar. Find the center of gravi
- Diamond-air 27221
Find the cut-off angle for the diamond-air pair. n_d = 2.42 α_m =? The absolute refractive index of light for air n = 1