Grade - examples - page 129

Expressions
Expression (3a-7).(3a+7) is identical with: ?
Jam
Jar with jam weighs 800 grams. Jam weighs three times as much as the empty glass. What is the weight of jam that is in the glass?
One-third
A one-third of unknown number is equal to five times as great as the difference of the same unknown number and number 28. Determine the unknown number.
Lottery
Fernando has two lottery tickets each from other lottery. In the first is 973 000 lottery tickets from them wins 687 000, the second has 1425 000 lottery tickets from them wins 1425 000 tickets. What is the probability that at least one Fernando's ticket w
Roof tiles
The roof has a trapezoidal shape with bases of 15 m and 10 m, height of roof is 4 meters. How many tiles will need if on 1 m² should be used 8 tiles?
Consecutive numbers
Sum of ten consecutive numbers is 105. Determine these numbers (write first and last).
Four families
Four families were on a joint trip. In the first family, there were three siblings, namely Alica, Betka and Cyril. In the second family were four siblings, namely David, Erik, Filip and Gabika. In the third family, there were two siblings, namely Hugo and
Prism - eq triangle
Calculate the volume and surface of the prism with the base of an equilateral triangle with side a = 4cm and the body height is 6cm.
Ten dices
When you hit ten dices at the same time you get average 35. How much do you hit if every time you get six, you're throwing the dice again?
Conference
148 is the total number of employees. The conference was attended by 22 employees. How much is it in percent?
Unknown number 7
16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
Farmers
Farmers loaded into a truck of fruit and vegetables intended for the store. 10 boxes of 5 kg pears, 8 boxes of 6 kg plums, 7 boxes 9 kg of carrots and 10 bags of 50 kg of potatoes. How many kilograms of fruit and vegetables loaded in total? How many kg cou
Circular lawn
Around a circular lawn area is 2 m wide sidewalk. The outer edge of the sidewalk is curb whose width is 2 m. Curbstone and the inner side of the sidewalk together form a concentric circles. Calculate the area of the circular lawn and the result round to 1
Timeage
Seven times of my age is 8 less than the largest two-digit number. How old I am?
Performance
Same number of tickets sold for 15 CZK, 20 CZK, 30 CZK and 40 CZK a total of CZK 13,230 on theatre performance. How many tickets were sold for this performance?
The result
How many times I decrease the number 1144 to get the result 22?
Students
In the front row sitting three students and in every other row 11 students more than the previous row. Determine how many students are in the room when the room is 9 lines, and determine how many students are in the seventh row.
Bus lines
Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
Octahedron
All walls of regular octahedron are identical equilateral triangles. ABCDEF octahedron edges have a length d = 6 cm. Calculate the surface area and volume of this octahedron.
Skiing meeting
On the skiing meeting came four friends from 4 world directions and led the next interview. Charles: "I did not come from the north or from the south." Mojmir "But I came from the south." Joseph: "I came from the north." Zdeno: "I come from the south." W

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