Examples for 8th grade - page 12
How much 60% solution and how much 35% solution is needed to create 100 l of 40% solution?
The lenght, width and height of a right prism are 18, 14 and 9 respectively. What is the lenght of the longest segment whose endpoints are vertices of the prism?
- Simply equation
Solve this equation for x: ?
- Oil rig
Oil drilling rig is 23 meters height and fix the ropes which ends are 8 meters away from the foot of the tower. How long are these ropes?
Bottle with cork cost 9.9 Eur. The bottle is 0.9 euros more expensive than cork. How much is a bottle and the cork?
If one side of the rectangle is larger 3-times and second 4-times, what percentage increases the area of rectangle?
- Five girls
Five girls traveling by bus. Each holds in each hand two baskets. In each basket are four cats. Each cat has three kittens. Two girls exits bus. How many legs are in the bus?
In the box are 6 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
How many 46% alcohol we need to pour into 3 liters 63% alcohol to get p3% of the alcohol? How many 52% alcohol we get?
What angle are between directions W (West) and SE (SouthEast) on the compass?
- Cylinder - A&V
The cylinder has a volume 253. The base has a radius 5. What is the area of surface of the cylinder?
The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first?
Mr. Robert and Mr. Norbert get together € 1400. The revenue split in the ratio of 4:3, depending upon each work. How many got each of them?
Mirka spent on a trip for gifts half pocket. For the third remain money bought a bagel. Six euros left her. How many euros had Mirka in pocket?
- Parquet floor
Three workers laid parquet floor for 3.646 hour. The first one would do this work alone 11 hours, the second in 12 hours. For how many hours would fulfill this work the third worker, if he worked alone?
- 4 pipes
The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
- Racing track
On the racing track circling three cars. The first passes one circuit for 8 seconds, the second for 16 seconds and a third for 15 seconds. a) Calculate number of seconds since the start to catch all three cars together for the first time again across the.
After death father (♱ 53) remained mother (his wife) and its 5 children. Inheritance by law is that in first mother will automatically get half of the property and other one half inherite by heirs witch are mother and her 5 children by same share. Cal
Product has been discounted twice by 14%. What is the total discount given?
The barrel is 239 litres of 31% acid. How many percent acid occurs when 88 litres revoke and replace it with the same amount of water?