Examples for 7th grade (seventh) - page 84

  1. Reducing scale
    map_mo I am sizing some landscaping and I measured everything for a 20 to 1 scale. I realized when I was done that it was at 30 to 1. How can I convert what I already have to 30 to 1. (Example, grass area is 22,871.6' at 20 to 1, how do you figure it out to be 30
  2. Birthday party
    influenza_1 For her youngest son's birthday party, mother bought 6 3/4 kg of hotdog and 5 1/3 dozens bread rolls. Hotdogs cost 160 per kilogram and a dozen bread roll costs 25. How much did she spend in all?
  3. Down syndrome
    gene Down syndrome is one of the serious diseases caused by a gene mutation. Down syndrome occurs in approximately every 550-born child. Express the incidence of Down's syndrome in newborns at per mille.
  4. To improper fraction
    fractal_15 Change mixed number to improper fraction a) 1 2/15 b) -2 15/17
  5. Customary length
    inch Convert length 65yd 2 ft to ft
  6. The lowest
    teplomer_20 The lowest temperature on Thursday was 20°C. The lowest temperature on Saturday was 12°C. What was the difference between the lowest temperatures?
  7. Mysterious number
    fun3_9 The magician thinks the number: "The mysterious number is first divided by minus five, dividing the result by three, multiplying the number by ten, and dividing the resulting number by minus four. This gives result 5. Can you reveal the mysterious number?
  8. Pencil cut
    tuzky_2 Veronika cut 10cm pencil. Each turn, the pencil was reduced by 0.2mm. She turned the pencil 100 times. How many centimeters has a pencil now?
  9. Unknown number
    zlomky_19 I think the number. I'll reduce it to its one-third. The result is then increased by one-third, and I get the number 12.
  10. Difference in temperatures
    teplomer_10 The temperature in the number line show minus 15 degree celsius and 8 degree celsius. What is the different between the temperatures?
  11. Melting point
    mercury-metal-Hg The melting point of mercury is -36°F and its boiling point is 672°F. What is the difference between the boiling point and the melting point?
  12. A man
    penize_49 A man spends 5/9 of his money on rent, and 5/16 of the remainder on electricity. If the final balance remaining is 550 find how much was spent on rent
  13. Two angles
    rt_1_1 The triangles ABC and A'B'C 'are similar. In the ABC triangle, the two angles are 25° and 65°. Explain why in the triangle A'B'C 'is the sum of two angles of 90 degrees.
  14. Last page
    books_44 Two consecutive sheets dropped out of the book. The sum of the numbers on the sides of the dropped sheets is 154. What is the number of the last page of the dropped sheets?
  15. Andre
    stamp_6 Andre, Thomas, and Ivan split 88 postage stamps in a 2:5:4 ratio. How much did Thomas get?
  16. Regrouping
    mixed_7 Subtract mixed number with regrouping: 11 17/20- 6 19/20
  17. Twenty
    rabbits_1 Twenty rabbits are put in 4 cells so that there are different number of rabbits in each cell contains at least 3 rabbits. What is the largest possible number of rabbits in one cell
  18. Taxi
    linear_eq_1 A taxi ride costs $3 plus $2.50 per mile. Write and Graph an equation in two variables that represents the total cost of a taxi ride.
  19. Maria
    green-grapes Maria has decided to plant grapes in the garden behind her house. His neighbor Ben has grown grapes successfully for a long time and has given Maria advice on how to plant vines. Ben told her to plant them 3 meters apart in rows that are also 3 meters apar
  20. Factors 2
    powers_2 A number has 3 identical factors. If 1 of them is 18. Find the number step by step

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