Examples for 8th grade
Number of examples found: 2686
- Cuboid box
How many m2 paper is needed for the sticking cuboid box of dimensions 50 cm, 40 cm and 30 cm? To the folds add one-tenth the area.
- Image scale
The actual image dimensions are 60 cm x 80cm and has a reduced size 3 cm x 4 cm. At what scale the image was reduced?
- Water pool
Pool with volume 990hl completely filled, if water flows by one tap 8 hours and by second tap 6 hours. First tap give 10hl more than second per hour. How many hl flows in each of them in an hour?
- Right triangle ABC
Calculate the perimeter and area of a right triangle ABC, if you know the length of legs 4 cm 5.5 cm and 6.8 cm is hypotenuse.
- Dining room
The dining room has 11 tables (six and eight seats). In total there are 78 seats in the dining room. How many are six-and eight-seat tables?
- RT 11
Calculate the area of right tirangle if its perimeter is p = 45 m and one cathethus is 20 m long.
Vector a has coordinates (8; 10) and vector b has coordinates (0; 17). If the vector c = b - a, what is the magnitude of the vector c?
- Inscribed rectangle
The circle area is 216. Determine the area of inscribed rectangle with one side 5 long.
- The conical
The conical candle has a base diameter of 20 cm and a side of 30 cm. How much dm ^ 3 of wax was needed to make it?
- Points on line segment
Points P & Q belong to segment AB. If AB=a, AP = 2PQ = 2QB, find the distance: between point A and the midpoint of the segment QB.
- Bronze medal
To produce 1 kg of bronze must be 0.95 kg copper, 0.04 kg of tin, 0.01 kg zinc. The bronze medal has a weight of 8.5 g. How much copper, tin and zinc does medal have?
- Flowerbed 2
Around the square flower bed in a park is sidewalk 2 m wide. The area of this sidewalk is 243 m2. What is the area of the flowerbed?
Of the girls who attend primary school are 30% blondes and 70% brunette. 81% blondes and 19% brunette has blue eyes. How many girls attending school altogether if 470 girls has blue eyes?
Calculate area of trapezoid ABCD with sides |AD|= 68 cm, |DC|=35 cm, |CB|=12 cm, |AB|=35 cm..
- Age of family
The age of father and son is in the ratio 10: 3. The age of the father and daughter is in ratio 5: 2. How old are a father and a son if the daughter is 20?
In what ratio must two sorts of sugar, costing #390 and #315 per kg respectively, be mixed in order to produce a mixture worth #369 per kg?
The boys and girls in the class formed without the rest of the fives, 2 girls and 3 boys. There are 6 girls missing to create mixed pairs (1 boy and 1 girl). How many girls are in the classroom?
Father said: "exactly after 56 hours we will sit down to Christmas Eve table" How was and what time it was when Father said this sentence? The Christmas Eve table they sit down at exactly 6 PM hour.
- Cuboid easy
The cuboid has the dimensions a = 12 cm, b = 9 cm, c = 36 cm. Calculate the length of the body diagonal of the cuboid.
- Spain vs USA
Spain lost to the US by 4 goals. In the match total fell 10 goals. How many goals gave the Spain and how the United States?