Examples for 8th grade - page 22
Can umbrella 75 cm long fit into a box of fruit? The box has dimensions of 390 mm and 510 mm.
- Trio 2
Decide whether trio of numbers is the side of a right triangle: 26,24,10.
How many raffle tickets must be purchased by Peter in raffle with issued 200 tickets if he wants to be sure win at least 3 price? In the raffle draws 30 prices.
First pump flows 16 liters per second into the basin by the second pump 75% of the first and by third pump half more than the second. How long will take fill basin by all three pumps simultaneously volume 15 m3 (cubic meters)?
Sisters Hanka and Vera goes mostly tograndmother by bicycle. Journey took Hanka 30 minutes and Vera 20 minutes. How long will Vera catch up with Hanka when started from home five minutes later than Hanka?
- Map 2
At what scale is made map if the distance 6.8 km corresponds on the map segment 4 cm long?
At the pharmacy are in one container 20% solution in the second 50% solution of disinfectant. They need to prepare 24 L of 36-percent solution. What amount of solution from each container is needed to mix?
Camel owner wants to get out of the city into oasis. He bought 3000 bananas, which wants to sell in oasis. However oasis from the city divided 1,000 kilometers of desert. Camel can carry at one time up to 1000 bananas, and for every kilometer traveled, ea
- Pyramid roof
1/3 of area of the roof shaped regular tetrahedral pyramid with base edge 10 m and height of 4 m is already covered with roofing. How many square meters still needs to be covered?
- Combinations of sweaters
I have 4 sweaters two are white, 1 red and 1 green. How many ways can this done?
- Sales off 2
Computer monitor sold for 8400 CZK in March. In April, dealer price decreased by 798 CZK. Calculate the percentage by which the price was reduced.
In a completely crowded resort was 30% from the Czech Republic quarter visitors were from Slovakia and the rest 135 came from Germany. What capacity have resort?
In the bag was to total 193 plums. Igor took 4 plums and Mary took 4/7 from the rest. How many plums remained in the bag?
A team of colleagues done the work in 20 days. After adding 2 colleagues from the beginning the work was completed in 15 days. How many members has the colleague team?
- Two workers
Two workers carry will do certain work for 12 days. After 8 days of working was one removed, and then the other finished the job alone in 10 days. For how many days would do this work alone each worker?
At this point, the first skier lead 14 km before the second skier and travels at a constant speed 13 km/h. The second skier rides at 19 km/h. How long take him to catch up the first?
How high is the building that throws horizontal shadow 58.5 m long at angle 36°36'?
- Sphere A2V
Surface of the sphere is 306 m2. What is its volume?
- Runners circle
Pepa circles the track in 36 seconds. Kamil in 42 seconds. They started together. How many seconds will meet again at the start?
- Journey to grandma
Daniel traveled to grandma. He travel 100 km along. Halfway travel by train, one quarter by bus, one tenth by the bicycle and the rest travel by car. How many km travel km by car?