# Examples for 7th grade (seventh) - page 68

1. Percents - easy How many percent is 432 out of 434?
2. Volume and area What is the volume of a cube which has area of 361 cm2?
3. 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. L
4. Proportion write the following proportion 8 is to 64 as to 2 is to x
5. Seagull Artificially created island in the shape of a circle with a radius of 50 m is overgrown with grass. The only exception is a landing area for helicopters in the shape of a rectangle measuring 15 m and 8 m. What is the probability that the flying seagull (wi
6. Boys and girls There are 28 girls in the hall. 5/7 of all children are boys. How many children and how many boys are there?
7. Broken tree The tree is broken at 4 meters above the ground and the top of the tree touches the ground at a distance of 5 from the trunk. Calculate the original height of the tree.
8. Study For 7 hours study, she scored a 75 so if she made 93 how many hours would she need to study?
9. Circle chord Calculate the length of the chord of the circle with radius r = 10 cm, length of which is equal to the distance from the center of the circle.
10. Bakery and flour The bakery tray for flour was filled to 3/4 volume. After removing 875 kg of flour, it was filled to only 2/5 of the volume. How many tons of flour is in the full tray?
11. Obtuse angle Which obtuse angle is creating clocks at 17:00?
12. The rope A 68 centimetre long rope is used to make a rhombus on the ground. The distance between a pair of opposite side corners is 16 centimetres what is the distance between the other two corners?
13. Alley Alley measured a meters. At the beginning and end are planted poplar. How many we must plant poplars to get the distance between the poplars 15 meters?
14. Trees A young tree is 16 inches tall. One year later, it is 20 inches tall. What is the percent increase in height?
15. Money split Anton and Ferko got 2,500 euros together. The amount was split in 1:4 ratio. How much did each get?
16. Equation Solve the equation: 1/2-2/8 = 1/10; Write the result as a decimal number.
17. Three painters The three painters have painted bridge. The first would work done in 5 days, the second in 6 days, and the third in 7.5 days. How long will the bridge work if they work together?
18. MO Z8–I–6 2018 In the KLMN trapeze, KL has a 40 cm base and an MN of 16 cm. Point P lies on the KL line so that the NP segment divides the trapezoid into two parts with the same area. Find the length of the KP line.
19. Shirt Mrs. Vítková bought each of his three children the same shirt paid CZK 1,000. Saleswoman she returned 568,60 CZK. What was the price of one shirt?
20. 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

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