Maths practice for 14 year olds - page 129 of 378
Number of problems found: 7553
- The painter
The painter lived to be 82 years old. In the 20th century, he lived 32 years longer than in the 19th century. In what year was he born?
- Divisions 43621
With a measuring range of 30mA, the hand points to 20 divisions out of 100 divisions of the scale. What current is measured?
- Probability 43581
What is the probability that the sum of 12 will fall on a roll of two dice? A. 1/6 B. 1/36 C. 1/18 D. 36
- Heads and legs
There are chickens and rabbits in the yard. Together, they have 108 legs and 33 heads. How many chickens are there? How many rabbits are there?
- Rotation 43561
The boy is sitting on a two-arm swing, and his seat is 300 cm away from the center of rotation. Its weight is 48 kg. The girl is sitting at the other end of the swing, and her mass is 36 kg. How far from the center of rotation must the girl sit for them t
- Photos
Three friends, Mirka, Lucka, and Hanka, collect photos. If Mirka had three more photos, she would have as many as Hanka. If Lucka had five photos less than she has, she would be like Hanka. How many photographs does each have if they have 431 together?
- Circumference 43531
A triangle with a circumference of 69 cm has one side three times shorter than the longest of them and the other 3 cm shorter than the longest of them. Find the area of the triangle.
- They bought
They bought the students a set of notebooks for 65 euros. The first set cost € 2 and the second € 3. There were five times as many two-euro as three-euro sets. How many sets of workbooks are there?
- Substitutes 43471
What pressure will the falling snow exert on the roof of the house? The weight of snow on the entire roof is 150 kg. The area of the lookout, covered with snow, is 10 m². - Don't forget the notation; the formula then substitutes the result.
- Crowns 43441
Petr, Jitka, and Karel have a total of 200 crowns. Petr has five crowns more than Karel. Jitka has 2x more than Karel. How many crowns does Karel have?
- The roof
The tower's roof has the shape of a regular quadrangular pyramid, the base edge of which is 11 m long, and the side wall of the animal with the base at an angle of 57°. Calculate how much roofing we need to cover the entire roof if we count on 15% waste.
- The square
The square oak board (with density ρ = 700 kg/m3) has a side length of 50 cm and a thickness of 30 mm. 4 holes with a diameter of 40 mm are drilled into the board. What is the weight of the board?
- 1200 screws
1200 screws are to be divided into three groups so that in the 1st group, there are 300 screws more than in the 2nd group, and in the 2nd group, 150 screws less than in the 3rd group. How many screws will be in each group?
- Altitude angle
In complete winds-free weather, the balloon took off and remained standing exactly above the place from which it took off. It is 250 meters away from us. How high did the balloon fly when we saw it at an altitude angle of 25°?
- Calculate 43331
From the lookout tower, 70 meters high, we see a man at a depth angle of 15 degrees. Calculate how far one stands from the base of the lookout tower. Draw and calculate.
- Inclination 43321
What percentage of the gradient should be indicated on the mark if the angle of inclination of the road is 6 ° 25'?
- Cone-shaped 43291
Calculate the volume and weight of a pile of cone-shaped sand with a diameter of 8m and a height of v = 4.5m; the density of sand is 1500kg/M cubic.
- The aluminum
We placed the aluminum object with a weight of 0.80 kg and a temperature of 250°C in the water with a weight of 1.6 kg and a temperature of 23°C. What is the system temperature after reaching equilibrium? We assume that the heat exchange occurred only bet
- The bath
The bath has water with a volume of 220 l and a temperature of 65°C. Find the mass m2 of water at 15°C to be poured, so the resulting temperature in the bath will be 40°C. We neglect the heat exchange between water and the environment. Water's
- Calculate
Two friends Mário and Jano lived on two different sides of a highway. They decided to find out how wide it was. Mário drew a picture, based on which they then made measurements the next day. They measured the values a =5m, b= 5.9 m, and d = 5 m. Calcula
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