Math practice for 13 year olds - page 357 of 362
Number of problems found: 7234
- Rectangular field
One dimension of the rectangular field is 56 m greater than the second dimension. If each side of the rectangle increases by 10 m increases, the surface field is 1480 m². Find dimensions of the field. - Determine the number
Determine the number x that x+8 is (7)/(5) from one half of 7 x -1. - Root
Use the law of square roots: cbrt (sqrt[2] (sqrt[4] (6))) = sqrt[n] (6) - Rates
When gas consumption, the consumer may choose one of two rates: rate A - which pays 0.4 € per 1 m³ of gas a flat monthly fee of 3.9 € (regardless of consumption) rate B - which pays 0.359 € per 1 m³ of gas a flat monthly fee of 12.5 € From what monthly co
- Center traverse
Does the middle traverse indeed bisect the triangle? - Diagonals of the rhombus
Calculate the height of the rhombus whose diagonals are 18 cm and 6 cm. - Number
Is number 2.8814789 irrational? - Chord
In a circle with a radius r=60 cm is the chord, 4× longer than its distance from the center. What is the length of the chord? - Box
Calculate the angle between box base 9 x 14 and body diagonal length 18.
- Rotating cone II
Calculate the area of the surface of a rotating cone with base radius r=15 cm and height h=13 cm. - Is right?
Is a triangle with sides 51, 56, and 77 right triangle? - Proof I
When added to the product of two consecutive integers larger one, we get the square larger one. Is this true or not? - Energy saving
They released three different independent inventions saving 15%, 17%, and 16% energy. Some considered that with the use of these inventions, the total savings would be 15% + 17% + 16% = 48%. Is this true? How much will the percent of energy save all three - Kitchen
The kitchen roller has a diameter of 72 mm and a width of 287 mm. How many square millimeters roll on one turn?
- Gear wheels
Two gear wheels, which fit together, have the number of teeth z1=117 and z2=70. Calculate the speed of the first wheel if the second wheel rotates 582 revolutions per minute. - Median
In the right triangle are sides a=96 dm b=31 dm. Calculate the length of the medians tc to the hypotenuse. - Secret number
Find the secret number n, which reversed decreases by 16.4 if the number increases by 16.4. - Seedcake
Seedcake costs 44 cents. How many minimum seedcakes must we buy that we can pay in cash, only whole euros? - Conserving water
Calculate how many euros are spent annually on unnecessary domestic hot water, which cools during the night in the pipeline. The residential house has 129 m of hot water pipelines 5/8" and the hot water has a price of 7 Eur/m³.
Calculate the triangle's heights ABC if the triangle's sides are a=26, b=81, and c=73.Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
