Math practice for 13 year olds - page 8 of 434
Number of problems found: 8667
- The average 16
The average of 50 numbers is 38. If the two numbers 45 and 55 are not considered, what will be the average of remaining numbers?
- Gain or loss
A man purchases a certain number of apples at 3/eur and same number of apples at 4/euros. He mixed them together and sells them at 3/euros. What is the gain or loss percent? Write answer as number, loss as negative, gain as positive percent.
- Freezing
A certain freezing process requires that room temperature be lowered from 40°C at the rate of 5°C per hour.What will be the room temperature 12 hours after the process begins?
- Time interval
Find the time interval between 7:40 AM and 1 : 20 PM.
- Angle of elevation
The angle of elevation of the top of an unfinished pillar at a point 150 m from its base is 30°. If the angle of elevation at the same point is to be 45°, then the pillar has to be raised to a height of how many meters?
- The distance 4
The distance between two towns is 120 km there are approximately 8 km in each 5 mi. Which measurement is closest to the number of miles between each two towns?
- Lemon tarts
A baker made some lemon tarts. He sold 40% of the tarts in the morning, 2/5 of the remaining tarts in the afternoon and had 54 tarts left. How many tarts did he bake altogether?
- A student 8
A student was asked to write 25 * 9² . By mistake he write 2592. Find the difference.
- Two trains 12
Two trains 128m and 132m long are running towards each other on parallel lines at 42km/h and 30km/h respectively. In what time will they clear of each other from the moment they meet?
- One combine
One combine harvester can harvest a field of corn in 4.5 hours. Another harvester can harvest the same field in 3 hrs. If the farmer uses the two harvesters at the same time. How long will it take to harvest the entire field?
- A tank 2
A tank can be filled by a pipe A in 3 hours and by pipe B in 5 hours. When the tank is full, it can be drained by pipe C in 4 hours. If the tank is initially empty and all three pipes are open, how many hours will it take to fill up the tank?
- Length measurement
Choose the measurement closest to 60 cm: ...
- The river
The river flows at 4 km/h. A boat can go downstream thrice as fast as upstream. Find the speed of the boat in still water.
- A tradesman
A tradesman marks his goods at 35% above the cost price and then allows a discount of 15%. Find his profit percentage.
- Two vertically
Two vertically opposite angles are (x-20)° and 85°; then, find the value of x.
- An examination
In an examination there were 1000 boys and 800 girls. 60% of the boys and 50% of the girls passed. Find the percent of candidates failed.
- The profit 4
By selling an article for 19.25 USD a trader makes a profit of 25% How much must he sell the article to make a profit of 40 %?
- Joseph 2
Joseph visits the club on every fifth day, Harry visits on every 24th day, and Susan visits on every ninth day. If all three of them met at the club on a Sunday, then on which day will they meet again?
- Central angle 2
What is the arc length of a circle with a radius of 12 cm and a central angle of 255 degrees? A. 8.5 cm B. 12π cm C. 24π cm D. 17π cm
- The cuboid 2
If the areas of three adjacent faces of a cuboid are 6,10,22 respectively then find the volume of the cuboid.
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