Examples for 8th grade - page 35
Albert, Beny, Cyril and Dan worked on summerjob. From the total revenue Albert received 2/5, Beny 1/6 , 3/10 Cyril and Dan the rest which is 324 euros. How many euros earned every one of them?
Solve following system of equations: 6(x+7)+4(y-5)=12 2(x+y)-3(-2x+4y)=-44
- Freight train
The train carries 525 tons of limestone in 29 wagons. Wagons are 15 tonne and 20 tons. How many is 15 ton and how many is 20 ton wagons?
- Acute angles
Sizes of acute angles in the right-angled triangle are in the ratio 1: 6. What is size of the larger of them?
- Football league
In the 4th football league plays each of the 16 participants with each opponent twice. For every victory gets 3 points, 1 point for a draw, a defeat none. After the competition was team with 56 points and 8 defeats at 6th place. How many times have won?
Vector a has coordinates (7; 16) and vector b has coordinates (15; -7). If the vector c = b - a, what is the magnitude of the vector c?
Rope with a bucket is fixed on the shaft with the wheel. The shaft has a diameter 60 cm. How many meters will drop bucket when the wheels turn 15 times?
The driver of a car is to get to 378 km distant city. From atlas found that 99 km will have to pass through the cities at average speed 48 km/h. Remainder of the journey pass outside the cities at average speed 117 km/h. Calculate how many hours it will ta
Roller has a diameter of 0.97 m and a width 169 cm. How many m2 of road level when he turns 68-times?
The country has 5.9 million citizens which 2.24 million are voters. Turnout was 39.9%. President R. F. was elected from 19 candidates for president and won with 28% of votes. Calculate what percentage of the country's citizens voted R.F. as president of
- Driving school
Driving final exam involving 17 attendants. The exam consists of three parts. 4 fails at test (quiz) and 3 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
What is the side length of the regular 5-gon inscribed in a circle of radius 11 cm?
The bridge arc has a span 157 m and height 5 m. Calculate the radius of the circle arc of this bridge.
- Monty Hall
Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. W
Video is 250% more expensive than tape recorder. How many percent is tape recorder less expensive than video?
- Free fall
Stephen fall from height 5 m. Calculate the speed he hit the ground when falling with acceleration g = 9.81 m/s2
Calculate how much land saw Felix Baumgartner after jump from 22 km above ground. The radius of the Earth is R = 6378 km.
- Euler problem
Someone buys a 720 tolars towels. If it was for the same money of 6 more towels, it would be 6 tolars cheaper each. How many were towels?
- Circle and angle
What is the length of the arc of a circle with radius r = 138 cm with cental angle 2.07 rad?
- Cube - angles
Calculate angle between the wall diagonal and cube base. Calculate the angle between the cube body diagonal and cube base.