Math practice for 13 year olds - page 365 of 423
Number of problems found: 8455
- Beer permille
In the 5 kg of the blood of an adult human after three 10° beers consumed in a short time is 6.6 g of alcohol. How much is it per mille?
- Chords centers
The circle has a diameter of 17 cm, upper chord |CD| = 10.2 cm, and bottom chord |EF| = 7.5 cm. The chords H and G midpoints are |EH| = 1/2 |EF| and |CG| = 1/2 |CD|. Find the distance between the G and H if CD II EF (parallel).
- Fifty-crown 2627
A notebook costs CZK m, and a pencil costs the same. The ruler costs CZK n. The brush costs CZK 6. Jirka bought 3 notebooks, 2 pencils, a ruler, and a brush. He paid with a fifty-crown note. How much did he get back?
- Passenger car and truck
From Kutna Hora left at 11:00 clock a truck at 60 km/h. At 12:30, behind him started the passenger car at an average speed of 80 km/h. At what time and how far from Kutna Hora overtake a passenger car truck?
- Two trains meet
From A started at 7:15, the express train at a speed of 85 km/h to B. From B, the passenger train started at 8:30 in the direction of A and at a speed of 55 km/h. The distance A and B are 386 1/4 km. At what time and distance do the two trains meet from B
- Cyclist vs car
The cyclist rode out of the city at 18 km/h. One hour 30 minutes behind him started the car and caught up with the cyclist in 50 minutes. How fast was driving the car? Where (what kilometer) from the city car overtook a cyclist?
- Tangents construct
The circle k is given k (S; 2.5 cm) and an outer line p. Construct a tangent t of the circle that has a line p angle 60°. How many solutions have the task?
- Combinations of sweaters
I have four sweaters: two white, one red, and one green. How many ways can you sort them out?
- Technical 2617
Pupils work in groups of two on technical work in the school to make a birdhouse. If Tomáš worked alone, he would make the booth in 4 hours. Richard would do it in 2 hours. If they work together, how many hours will it take them to complete it?
- Boots
Master shoemaker has three apprentices. First, do one pair of boots for two days, second for one day, and third for 1.5 days. How long would it take to make a couple of boots if they worked together?
- O'clock 2614
One pump fills the school pool in 15 hours. The school bought another pump that would fill the pool in 10 hours. What is the latest time to start filling the pool if they want to have it filled at eight o'clock in the morning and use both pumps?
- Determine 2611
1. Determine a number with the same result if we multiply it by ten as if we add 10 to it. 2. Věra is twice as old today as her sister Jitka. In five years, Jitka will be only 1/3 years younger than Věra. How old are Věra and Jitka today? 3. Find the pair
- Novak
Novak needed to dig up three of the same pit in the garden. The first pit was dug father alone for 15 hours. His second dig son helped him, and it did that in six hours. The third pit was dug son himself. How long does it take him?
- Cyclist
The cyclist rode two-fifths of the way the first day. On the second day drove 5 km less while traveling three-eighths of the route. How many kilometers does he have to finish the target?
- Rhombus
ABCD is a rhombus, ABD is an equilateral triangle, and AC is equal to 4. Find the area of the rhombus.
- Banknotes
$ 1390 was collected. How much was in $20 notes, and how many in $50 notes in that order? How many solutions exist?
- Outer contact of circles
Construct a circle k1 (S1; 1.5 cm), k2 (S2; 2 cm), and K3 (S3; 2.5 cm) so that they are always two outer contacts. Calculate the perimeter of the triangle S1S2S3.
- Cat
Half of the rest postpone a new smartphone for one-fifth of the monthly pocket money contributed to Maros for food for his cat. The remaining € 8 is spent. How much pocket money gets Maros a month?
- Circumference parallelogram
Calculate the circumference and area of the parallelogram ABCD if side a = 72 cm, height v = 4.3 cm, and second side b = 6 cm.
- Shoes and slippers
Shoes were three times as many as slippers. If shoes were cheaper by 120, they would be twice as expensive as slippers. How much did the shoes cost, and how much did the slippers?
Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question.