Math practice for 13 year olds - page 2 of 420

Number of problems found: 8385

Equilateral RT
On a right triangle, side a is 12, and side b is 12. What is side c?
Four plates
Four equal maximum sized circular plates are cut off from a square paper sheet of area 784 sq cm. Calculate the circumference of each plates.
Length units
How many times inch and a half go to the 12 feet?
Three in a ratio
If A is 40% more than B, B is 20% less than C then, find the ratio A : C.
School - boys:girls
In a school 10% of boy is equal to the 1/4 of number of girls and 10% of the number of girls is equal to the 1/25 of boys. Find the ratio between the number of boys and girls.
Eva wraps
Eva wraps a gift box in the shape of a right rectangular prism. The figure shows a net for the gift box. How much wrapping paper did she use, in square meters?
A solid
A solid is in the shape of a cone standing on a hemisphere with both their radii being equal to 1 cm and the height of the cone is equal to its radius. Find the volume of the solid .
Compare ratios
Is ratios 4:7 and 16:19 equivalent?
The profit 6
A man sells an article at a profit of 20%. If he had bought it at 20% less and sold for $5 less, he would have gained 25%. Find the cost price of the article.
A train 6
A train covers a distance 10km, 20km, and 30km in 50 kmph, 60 kmph and 90 kmph respectively. Find the average speed of the train (in km/h).
The surface 5
The surface area of a cylinder is 6140 cm², and the radius is 25 cm. What is the height?
A building
A building has a height of 125 meters and a length of 80 meters. On a scale drawing of the building, the height of 25 centimeters. What is the length of the building on the scale drawing in centimeters?
A watch
If a watch is sold at 60 USD, there is a loss of 15%, for a profit of 2%, the watch is to be sold at how many USD?
A rope for cow
Find the length of a rope by which a cow must be tethered in order that it may be able to graze an area of 154 sq m .
The average 19
The average age of a class was 15 years. When 5 boys whose average age was 12 years 6 months were admitted in the class, the average was reduced by 6 months. How many students were there in the class originally?
The Earth and Moon
The diameter of the Moon is approximately 1/4 of the diameter of the Earth. What fraction of the volume of the Earth is the volume of the Moon?
The shadow 2
The shadow of a tower standing on a level ground is found to be 40 m longer when the Sun’s altitude is 30° than when it is 60°. Find the height of the tower.
Journey trip
A man performs 2/15 of the total journey by rail, 9/20 by bus and the remaining 10 km, on the cycle. What is his total journey?
Salaries - ratio3
The salaries A, B, C are in the ratio 2 : 3 : 5. If the increments of 15%, 10% and 20% are allowed respectively in their salaries, then what will be new ratio of their salaries?
Goods train
A goods train runs at the speed of 72 kmph and crosses a 250 m long platform in 26 seconds. What is the length of the goods train?

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