Examples for 8th grade - page 79
- Pyramid Z8–I–6
Each brick of pyramid contains one number. Whenever possible, the number in each brick is lowest common multiple of two numbers of bricks lying directly above it. That number may be in the lowest brick? Determine all possibilities.
- Diagonals of diamond
Find the area and circumference of the diamond ABCD with 15m and 11m diagonals.
I have a box with two hundred pieces of gloves in total, split into ten parcels of twenty pieces, and I sell three parcels. What percent of the total amount I sold?
- Repair company
The company repairs cars. The first day repair half of the contract second day, the half of the rest and third day 6 residue cars. How many total cars company repaired?
Dana, Dalibor and Michael have a combined 57 years. Dana is five years older than Dalibor, but Dana is five years younger than Michael. Determine how old is Dana, Dalibor and Michael.
- Hockey match
The hockey match ended with result 3:1. How many different storylines may have the match?
In the factory workers work in three shifts. In the first inning operates half of all employees in the second inning and a third in the third inning 200 employees. How many employees work at the factory?
- Circle's chords
In the circle there are two chord length 30 and 34 cm. The shorter one is from the center twice than longer chord. Determine the radius of the circle.
- Water wessel
The vessel containing water has a weight 19 kg. After pouring half the water its weigth 11 kg. What is the weight of the empty vessel?
- Loading car
The car was loaded with 78 boxes weighing 19 kg. How many 25kg boxes can load if the total weight is the same?
- The plan
Students have collected 48 kg of paper which is 16% of the plan. How many kg of paper still have to collect to fulfill the plan?
- Water reservoir
The reservoir shape of a cylinder having a diameter 8 m and a height 2.8 m. The device indicates that the reservoir contains 800 hectoliters of water. Calculate how much % of volume is used.
- Job task
After two hours and 40 minutes the job is finished. Compared to last year we were 40 minutes faster. What is the percentage increase to our performance?
- Three children
3 children eat 8 chocolates in 6 days. How many chocolates 6 children eat in 18 days?
Marry and John together weighing 49 kg. Their weights are in ratio 1:6. Determine their weights.
- 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.
- Sales off
Goods is worth € 31 and the price of goods fell two weeks in a row by 10%. How many % decreased overall?
Mom is 42 years old and her daughters 13 and 19. After how many years will mother as old as her daughter together?
- Combinations of sweaters
I have 4 sweaters two are white, 1 red and 1 green. How many ways can this done?
- Cyclist vs boat
The cyclist wants to ride a short distance by boat, but when he stops at the pier, the boat does not pick up passengers yet and is preparing to leave. The cyclist decides that the boat will catch up at the next stop. The stop is 12km far along the water an