Examples for 7th grade (seventh) - page 75

  1. Dd 2-digit numbers
    numbers_49 Find all odd 2-digit natural numbers compiled from digits 1; 3; 4; 6; 8 if the digits are not repeated.
  2. My father
    tree3_2 My father has a big farm. 6/8 of it were planted with mango trees, 1/2 of the remainder are guava trees and the rest 10 trees are santol trees. What is the number of all trees?
  3. Bus vs train
    Clock0400_1 Milada took the bus and the journey took 55 minutes. Jarmila was 1h 20 min by train. They arrived in Prague at the same time 10h45 min. At what time did each have to go out?
  4. Dinosaurs
    dino More than 30 and less than 60 dinosaurs have met at the pond. A quarter of them bathed and 1/7 saws and the rest gripped. How many were at the pond? How many were there?
  5. Together 3
    painter_8 If Sally can paint a house in 4 hours, and John can paint the same house in 6 hours, how long will it take for both of them to paint the house together?
  6. Trapezium 2
    trapezium_3 Trapezium has an area of 24 square cms. How many different trapeziums can be formed ?
  7. Seamstress
    textiles_2 The seamstress cut the fabric into 3 parts. The first part was the eighth fabric, the second part was three-fifths of the fabric and the third part had a length of 66 cm. Calculate the original length of the fabric.
  8. Orchard
    jablone_8 One-eighth of the trees in the fruit plant in winter froze and one-twelfth of damaged disease and pests. Healthy trees remained 152. Is it enough to supply 35 trees to restore the original number of trees in the orchard?
  9. Sugar production
    cukrrka_1 From 1 ton of beet, 150 kg of sugar is produced. To clean 1 ton of sugar 450 kg of lime is consumed. Calculate how many kgs of lime is consumed when processing 1 ton of sugar beet?
  10. Counting number
    numbers2_49 What is the smallest counting number divisible by 2,5,7,8 and 15?
  11. Cuboid
    kvader11 The sum of the lengths of the three edges of the cuboid that originate from one vertex is 210 cm. Edge length ratio is 7: 5: 3. Calculate the length of the edges.
  12. Pins 2
    pin_keyboard how many different possible 4 digits pins can be found on the 10-digit keypad?
  13. Sale
    usd A camera has a listed price of $751.98 before tax. If the sales tax rate is 9.25%, find the total cost of the camera with sales tax included.
  14. Cube edges
    cube_shield_3 The sum of the lengths of the cube edges is 42 cm. Calculate the surface of the cube.
  15. Clock hands
    clocks2_16 The second hand has a length of 1.5 cm. How long does the endpoint of this hand travel in one day?
  16. Train and walker
    trains_6 Walker passes an hour 5 km. Express train per hour 100 km. Walker went 4 hours. How many minutes took the distance express train?
  17. Withdrawal
    penize_13 If I withdrew 2/5 of my total savings and spent 7/10 of that amount. What fraction do I have in left in my savings?
  18. Cyclist 9
    cyclist_33 A cyclist travels at a a speed of 4.25 km per hour. At that rate, how far can he travel in 3.75 hours?
  19. Pupil age
    age_6 I am a pupil of the primary school, I spent 1/4 of my age on the exercise of parents with children, 1/3 on drawing, 1/6 on flute. I did not have a ring for the first three years of my life and never went to two rings at once. How old am I?
  20. Harvesters
    kombajn_10 The first harvester will harvest the grain from the field in 20 hours, the second, the more powerful in 10 hours. How long will take harvest this field by both harvesters, if the second harvester has to be set up first and this takes 2 hours? The first har

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