Math practice for 13 year olds - page 7 of 362
Number of problems found: 7234
- A recycling
A recycling bin contained 40 pounds of plastic in October and 50 pounds of plastic in November. By what percentage did the amount of plastic increase from October to November? - Automobil
The car traveled three quarters of the total journey at a speed of 90 km/h and the remaining part of the journey at a speed of 50 km/h. Find its average speed. - The world record
The world record for the longest dogtail is 77/100 meters. The previous record was 1/20 meter shorter than the current record. Was the previous record holder longer than 3/4 meter? - 15 years
15 years hence, a man will be just 4 times as old as he was 15 years ago. Find his present age.
- The dimensions
The dimensions of a rectangular piece of paper are 22 cm × 14 cm. It is rolled once across the breadth and once across the length to form right circular cylinders of biggest possible surface area. Find the difference in volumes of the two cylinders that w - Consecutive odd nums
Sum of four consecutive odd numbers is 40. Find the numbers. - Time and distance
A man walking at a speed of 4 km/h can reach a destination in 3 hours. If he increases his speed by 1 km/h, how much time will he save? - Spheres to cone
Two solid spheres of radii 2 cm and 4 cm are melted and recast into a cone of height 8 cm. Find the radius of the cone so formed. - A train 3
A train takes 3 hours to go from one station to another station. If its speed is decreased by 12 km/h then the journey time will increase by 45 min. What is the distance between the two stations?
- The remainder
Find the remainder if 17²00 is divided by 18. - A contractor 2 A contractor has to complete his contract in 92 days. 234 men were set to do the work, each of them works for 16 hours/day. After 66 days, 4/7 of the work is completed. How many additional men may be employed, so that the work may be completed in time, ea
- 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. - Number of sides
Find the number of sides of a regular polygon whose each exterior angle has a measure of 45°.
- 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 was asked to write 25 * 9² . By mistake he write 2592. Find the difference.Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
