# Examples for 8th grade - page 27

- Kitchen

Kitchen roller has a diameter 85 mm and width of 337 mm. How many square millimeters roll on one turn? - Gear wheels

Two gear wheels, which fit together have number of teeth z_{1}=132 and z_{2}=123. Calculate the speed of the first wheel, if the second wheel rotates 247 revolutions per minute. - Event probability

The probability of event G in 9 independent experiments is 0.48. What is the probability that the event G occurs in one experiment (probability is same)? - Rectangle

Area of rectangle is 1430. Its length is 29 larger than the width. What are the dimensions of the rectangle? - Smallest internal angle

Calculate what size has the smallest internal angle of the triangle if values of angles α:β:γ = 3:4:8 - Mother and daughter

The ratio of years mother and daughter is 5:2. After 7 years the ratio is 2: 1. How many years ago daughter was born? - Two looms

On two different looms with different performance can be make required quantity of textile in 6 hours when both work together. On the first machine this quantity of the textile can make in 10 hours. How long should take make same quantity of textile on a s - Probability - tickets

What is the probability that when you have 25 tickets in 5000 that you wins the first (one) prize? - Water pool

What water level is in the pool shaped cuboid with bottom dimensions of 25 m and 10 meters, when is 3750hl water in the pool. - Painting school

Redecoration school had scheduled for four crew to 10 days. After two days a single worker ill. For how many days the school was painted when remain workers working with the same tempo? - Lenka and money

When Lenka bought pants from 1/3 of her savings shirt from 1/5 and 1/8 spent at the hairdresser, she is left 328 Kč. How much money was saved? How much hairdresser cost? - Mushrooms from the forest

Magda and Tereza goes to pick mushrooms. Total found 70 mushrooms. Magda found that between fungi found 5/9 bedel. Tereza discovered that she found among fungi are 2/17 champignons. How many mushrooms found Magda? - Sisters

Sisters Zuzka Lenka and Vierka has save for a new bike. Zuzka save € 90, Lenka save € 90 and Vierka save € 82. Missing 30% gave them their mother. What is the price of the bike? - Circles

Area of circle inscribed in a square is 6. What is the area of a circle circumscribed around a square? - Tourists

From the cottage started first group of tourists at 10:00 AM at speed 4 km/h. The second started after them 39 minutes later at speed 6 km/h. How long and how many kilometers from the cottage will catch the first group? - Hřiště

Map scale is 1: 1000. The playground is rectangular and on the map has dimensions 10 cm and 5 cm What is area of playground in square meters in reality? - Mother and daughter

Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)? - Barbara

Barborka goes to school with backpack that was 3 - times more expensive than a bag slipper. If backpack was 33 euros cheaper it was cost same as bag slipper. How many cost backpack and how many bas slipper? - Task of the year

Determine the number of integers from 1 to 10^{6}with ending four digits 2001. - Balls

Three metal balls with volumes V_{1}=41 cm^{3}V_{2}=58 cm^{3}and V_{3}=83 cm^{3}melted into one ball. Determine it's surface area.

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