Examples for 7th grade (seventh) - page 70

  1. Thunder and lightning
    lightning There was a glimpse of the sky and we hear a thunder in 4.5 seconds. The light spreads at 300,000 kilometers per second, so we can assume the flash instantly without delay. However, the speed of the sound is much smaller in the air one third of a kilomete
  2. Three painters
    workers_37 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?
  3. Family 8
    family_19 Father is 38 years old, daughter 12, son 14. How many years will father have as many years as his children together?
  4. Lcd3
    lcd What is LCD of the equation of ? ? And what is x?
  5. Photo enlarge
    photo Mark wants to enlarge a 4-inch by 6-inch photo so that it has a height of 15inches. Use a ratio table to determine the new width of the photo.
  6. Candy
    friends Peter had a sachet of candy. He wanted to share with his friends. If he gave them 30 candies, he would have 62 candies. If he gave them 40 candies, he would miss 8 candies. How many friends did Peter have?
  7. Two cuboids
    cuboid_13 Find the volume of cuboidal box whose one edge is: a) 1.4m and b) 2.1dm
  8. Unknown numbers
    eq222_3 The sum of two consecutive natural numbers and their triple is 92. Find these numbers.
  9. Soda
    soda_water A pack of 12 sodas cost 5.04. What is the unit rate in dollars per soda?
  10. Clubhouse
    stol_2 There were only chairs and table in the clubhouse. Each chair had four legs, and the table was triple. Scouts came to the clubhouse. Everyone sat on their chair, two chairs were left unoccupied, and the number of legs in the room was 101. How many chairs w
  11. Rainfall
    cumulus How many liters of water did fell in a 32m long and 8m wide garden, if 8mm of rain fell?
  12. Bathroom 2
    tiles_5 A bathroom is 2.4 meters long and 1.8 meters wide. How many square tiles 1 dm on each side are to be used to cover it?
  13. Five pumps
    nadrz_14 The water tank is filled with two pumps in 48 minutes. How long would it take to fill it with 5 same pumps?
  14. Suzan
    children2_3 Susan's age will be after 12 years four times as much as twelve years ago. How old is Susan now?
  15. Trapezoid ABCD
    trapezium_2 ABDC is a trapezoid in which AB and CD are parallel sides measuring 6 and 9 respectively. Angles ABC and BCD are both right angles. Find the length of segment BD.
  16. Trapezium bases
    lichobeznik_7 Find the trapezium height if a = 8 cm and c = 4 cm if its content 21 square centimeters.
  17. Unknown number
    fractions_6 I think the number - its sixth is 3 smaller than its third.
  18. Square area
    100-square Complete the table and then draw each square. Provide exact lengths. Describe any problems you have. Side Length Area .
  19. Summands
    magic Find two summands of the number 42, so that its product is minimized.
  20. Cubes into cuboid
    cubes_21 How many 12 centimeter cubes fit into the block (cuboid) with 6dm, 8,4dm and 4,8?

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