# Examples for 7th grade (seventh)

1. Lcm of three numbers
What is the Lcm of 120 15 and 5
2. One deci
Wine 0,375 l costs 2040 CZK. How much does 1 dl cost?
3. Two boats
The sightseeing boat sail at 25 km / h. The cruise take 6 hours. How long the another boat sails at 60 km/h?
4. Pond
A pond with two open floodgates will emptied in 20 days. A larger floodgate will emptied whole pond in 30 days. For how long would he be emptied with a smaller floodgate.
A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
6. Pumping
The tank is filled with a larger pump in 12 hours and with scond pump in 15 hours. For how long does the tank fill when both pumps are switched on at the same time?
7. Trench
The trench is a four-sided prism. The cross section has a trapezoidal shape with basements of 4m and 6m, the length of the trench is 30m. What is the depth of the trench if we dig 60,000 l of soil.
8. Pins 2
how many different possible 4 digits pins can be found on the 10-digit keypad?
9. A map
A map of size 60cm by 25cm is reduced in the ratio of 3:5, twice. What are the new dimensions?
10. Cuboid
Cuboid has a surface of 516 cm2. Side a = 6 cm and b = 12 cm. How long is the side c =?
11. Surface of cuboid
Find the surface of the cuboid if its volume is 52.8 cm3 and the length of its two edges is 2 cm and 6 cm.
12. Type of triangle
How do I find the triangle type if the angle ratio is 2:3:7 ?
13. Volume of cube
Solve the volume of a cube with width 26cm .
14. Inter city bus
The inter city bus leaves Suva at 10.00am and reaches Nadi at 1.00pm covering a distance of 219km. How long did it take to reach the bus Nadi?
15. Trapezoidal prism
Calculate the surface of the quadrilateral prism ABCDA'B'C'D 'with the trapezoidal base ABCD. The height of the prism is 12 cm; ABCD trapezoidal data: AB base length is 8 cm, CD base length is 3 cm, BC arm length is 4 cm, and AC diagonal length is 7 cm.
16. Pills
If it takes 20 minutes to run a batch of 100 pills how many minutes would it take to run a batch of 50 pills
17. Tailor
From the rest of the cloth tailor could cut off either 3 m in men's suits without vest or 3.6 m with vest. What shortest possible length could the rest of the cloth have? How many suits a) without a vest b) with vest could make the tailor from the r
18. Guess a fraction
Tom was asked to guess a fraction. The sum of 1/2 the numerator and 1/3 of its denominator is 30. If Tom subtracts 36 from its denominator, the fraction becomes 1/3. What is the fraction that Tom was asked to guess? (Leave your answer in simplest form)
19. Roses 2
Aunt Rose went to the flower shop to buy a bouquet with three roses. The flower shop had white, yellow and red roses. How many different flowers bouquet can a flower make for Aunt Rose create? Write all the bouquet options.
20. Triangular prism
Calculate the volume and surface of the triangular prism ABCDEF with base of a isosceles triangle. Base's height is 16 cm, leg 10 cm, base height vc = 6 cm. The prism height is 9 cm.

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