Examples of equations for 7th grade (12y)

Number of problems found: 551

  • Unknown number 7
    percents2_9 16% of the unknown number is by 21 less than unknown number itself. Determine the natural unknown number.
  • Testing
    test_3 Students of high school have 10 points for each good solved task. The wrong answer is deducted by 5 points. After solving 20 tasks, student Michael had 80 points. How many tasks did he solve correctly and how many wrong?
  • Sugar
    cukr Sugar factory produced 127 tons of sugar in 1 day at 14% sugar content . How many tons of pure beet sugar factory processed in 1 day?
  • Translations
    translation If I going to translate the book 6 pages per day I translate it 4 days earlier than if I translated 5 pages a day. If I translate 4 pages a day I translate it for how many days.....?
  • Right triangle Alef
    r_triangle The obvod of a right triangle is 84 cm, and the hypotenuse is 37 cm long. Determine the lengths of the legs.
  • The plan
    zber Students have collected 48 kg of paper which is 16% of the plan. How many kg of paper still have to collect to fulfill the plan?
  • Children
    weight_1 Margaret and Zdena weigh the same and Petra 3 kg more. Together weigh 156 kg. How much do they weigh?
  • TV commercials
    ad_on_TV For the typical one-hour prime-time television slot, the number of minutes of commercials is 3/8 of the minutes of the actual program. Determine how many minutes of the program are shown in that one hour.
  • Paddlers
    vodacky Students of canoeists trip traveled in three days 102 km. Second day traveled 15% more than first day and at the third day 9 km over the second day. How many kilometers traveled each day?
  • Bonus
    moeny The gross wage was 1323 USD including 25% bonus. How many USD were bonuses?
  • Chicken
    sliepka I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
  • The creek
    potok Workers cleaned the creek within 3 days. The first day cleanse one-fifth the length of the creek, the next day 40% of the length of the stream and the third day 8 km length of the creek. How long is a creek?
  • Train
    High-Speed-Train A passenger train traveled for 2 hours 74 km. 3.1 hours after its departure started fast train and caught it on 186 km. How many km/h is different its average speeds?
  • Store
    pave One meter of the textile was discounted by 2 USD. Now 9 m of textile cost as before 8 m. Calculate the old and new price of 1 m of the textile.
  • Pumps A and B
    pump_2 Pump A fill the tank for 12 minutes, pump B for 24 minutes. How long will take to fill the tank if he is only three minutes works A and then both pumps A and B?
  • Trapezoid ABCD v2
    trapezium_table Trapezoid ABCD has length of bases in ratio 3:10. The area of riangle ACD is 825 dm2. What is the area of trapezoid ABCD?
  • Norm
    rajcata Three workers planted 3555 seedlings of tomatoes in one dey. First worked at the standard norm, the second planted 120 seedlings more and the third 135 seedlings more than the first worker. How many seedlings were standard norm?
  • Real estate
    house Residential house has three entrances numbered by odd numbers arithmetic progression. The sum of the two numbers on the corner entrances is 50. Calculate the highest of this three numbers.
  • Flour
    vaha_10 Kim needs 3/4 cup of flour to make 12 cookies. How much flour would she need to make 60 cookies?
  • Tributaries
    pritok The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?

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