# Grade - examples - page 100

- Energy saving

They were released three different, independent inventions saving 12%, 15% and 25% energy. Some considered that while the use of these inventions, the total savings will be 12% + 15% + 25% = 52%. Is this true? How much percent of energy will save all thre - Average speed

What is the average speed you have to move the way around the world in 80 days? (Path along the equator, round to km/h). - Pump

From the pump in the yard dripping water. Every drop is 1 ml. How many drops will be necessary before filling a bucket with a volume of 10 l? Calculate how long it will fulfill the bucket when drops fall each second. - Colour - billboard

Shelftalker has the shape of a parallelogram. Its length is 4.9 m and the corresponding height is 3.5 meters. Calculate how much (kg) paint must purchase to redecoration if 1 kg cover 4 m^{2}of shelftalker surface. - Internal and external angles

Calculate the remaining internal and external angles of a triangle, if you know the internal angle γ (gamma) = 34 degrees and one external angle is 78 degrees and 40 '. Determine what kind of triangle it is from the size of its angles. - Areaf of ST

It is given square DBLK with side |BL|=13. Calculate area of triangle DKU if vertex U lie on line LB. - Dusan

a) Dusan break two same window, which has triangular shape with a length of 0.8 m and corresponding height 9.5 dm. Find how many dm^{2}of glass he needs to buy for glazing of these windows. b) Since the money to fix Dusan has not, must go to the paint job - Cone

Into rotating cone with dimensions r = 8 cm and h = 8 cm incribe cylinder with maximum volume so that the cylinder axis is perpendicular to the axis of the cone. Determine the dimensions of the cylinder. - Cube 9

What was the original edge length of the cube if after cutting 39 small cubes with an edge length 2 dm left 200 dm^{3}? - Triangle IRT

In isosceles right triangle ABC with right angle at vertex C is coordinates: A (-1, 2); C (-5, -2) Calculate the length of segment AB. - Alcohol 2

Two types of alcohol one 63% and second 75% give 20 liters of 69% alcohol. How many liters of each type are in the mixture? - Three elephants

Three elephants eat three piles of hay in 150 minutes. For how long does 96 elephants eat 96 stacks of hay? - Three numbers

Create from digits 1-9 three-digit numbers with their sum the smallest. What value is the sum of these numbers? (Use each digit only once) - Television

When we add to the difference between the numbers 1704 and 654 the difference numbers 14920 and 14042, we get a year in which television was invented. How many years people known the TV? - Star

Calculate the content of the shaded part of square with side 19 cm. - Quadratic equation

Quadratic equation ? has roots x_{1}= 80 and x_{2}= 78. Calculate the coefficients b and c. - Isosceles triangle

Calculate area and perimeter of an isosceles triangle ABC with base AB if a = 6 cm, c = 7 cm. - 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? - 6-gon

Perimeter of regular hexagon is 113. Calculate its circumradius (radius of circumscribed circle). - Medicine

We test medicine on 6 patients. For all drug doesn't work. If the drug success rate of 20%, what is the probability that medicine does not work?

- «
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
- 105
- 106
- 107
- 108
- 109
- 110
- 111
- 112
- 113
- 114
- 115
- 116
- 117
- 118
- 119
- 120
- 121
- 122
- 123
- 124
- 125
- 126
- 127
- 128
- 129
- 130
- 131
- 132
- 133
- 134
- 135
- 136
- 137
- 138
- 139
- 140
- 141
- 142
- 143
- 144
- 145
- 146
- 147
- 148
- 149
- 150
- 151
- 152
- 153
- 154
- 155
- 156
- 157
- 158
- 159
- 160
- 161
- 162
- 163
- 164
- 165
- 166
- 167
- 168
- 169
- 170
- 171
- 172
- 173
- 174
- 175
- 176
- 177
- 178
- 179
- 180
- 181
- 182
- 183
- 184
- 185
- 186
- 187
- 188
- 189
- 190
- 191
- 192
- 193
- 194
- 195
- »

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.