System of equations - 8th grade (13y) - math problems

Number of problems found: 436

  • Father and son
    age When I was eight years old, my father was 30 years old. Today, my father is 3 times more than me. How old am I?
  • Railway embankment
    rr_lichobeznik The section of the railway embankment is an isosceles trapezoid, the sizes of the bases of which are in the ratio 5: 3. The arms have a length of 5 m and the height of the embankment is 4.8 m. Calculates the size of the embankment section area.
  • A bottle
    flasa A bottle full of cola weighs 1,320 g. If we drink three-tenths of it, it will weigh 1,008g. How much does an empty bottle weigh?
  • Aunt Rose
    eura Aunt Rose gave $2500 to Mani and Cindy. Mani received $500 more than Cindy. How mich did Cindy received?
  • Side lengths
    triangles_1 In the triangle ABC, the height to the side a is 6cm. The height to side b is equal to 9 cm. Side "a" is 4 cm longer than side "b". Calculate the side lengths a, b.
  • Trio ratio
    minca Hans, Alena and Thomas have a total of 740 USD. Hans and Alena split in the ratio 5: 6 and Alena and Thomas in the ratio 4: 5. How much will everyone get?
  • Bike ride
    car Marek rode a bike ride. In an hour, John followed him on the same route by car, at an average speed of 72 km/h, and in 20 minutes he drove him. Will he determine the length of the way that Marek took before John caught up with him, and at what speed did M
  • When I
    age When I am as old as my older brother is today, my brother will be twice as old as I am today. a) How old is my brother if I am 8 years old today? b) How old am I if my brother is 21 today?
  • Candies
    oriesky_3 In the confectionery, the price for 1 kg of pistachio candies cost CZK 360, and the price for 1 kg of hazelnut candies was CZK 280. Mixing these two types of sweets created a box of chocolates. How many grams of pistachios and how many grams of hazelnut c
  • The dormitory
    hotel_7 The dormitory accommodates 150 pupils in 42 rooms, some of which are triple and some are quadruple. Determine how many rooms are triple and how many quadruples.
  • Buttons
    oblek Men's shirt has sewn 9 buttons and blouse 3 buttons. Together they sewed 60 pieces and consumed 390 buttons. How many shirts?
  • Two accounts
    bankovka Two accounts in the bank, one per year interest 2%, the second 3%. Total interest income 1900 USD. If interest rates were reversed, the yield would be USD 200 higher. What are the amounts on each account?
  • Sow barley
    kombajn Farmers wanted to sow barley within 13 days. Due to the excellent weather, they managed to exceed the daily plan of sowing by 2 ha and therefore finished sow grain in 12 days. How many hectares of land did they sow with barley?
  • Jane plants
    flowers_8 Jane plants flowers in the garden. If she planted 12 every hour instead of 9 flowers, she would finish with the job an hour earlier. How many flowers does she plant?
  • In the classroom
    skola_1 There are 30 boys and a few girls in the class. In the six months, 28 boys and all girls benefited, which was 95% of all pupils. How many pupils are there in the classroom?
  • Twelve ties
    kravata The price of 12 ties before the discount was the same as 15 ties after discount. Calculate the price of 1 tie after discount, if you know that the discount price of one tie fell by 40 CZK?
  • Three brothers
    family_13 The three brothers have a total of 42 years. Jan is five years younger than Peter and Peter is 2 years younger than Michael. How many years has each of them?
  • Two numbers
    plusminus The difference between the two numbers is 74. If we divide a larger number by a smaller one, we get a quotient 7 and the rest of 2. Determine both numbers.
  • Mr and Mrs
    clocks2_8 Mr. Calda and Mrs. Cald have a total of 139 years. How many years have when we know that Mr. Calda is 9 years older than Mrs. Cald
  • Two melons
    melon_1 There are 2 melons in the box. Together they weigh 11kg. The weight of green is 3 kg less than three times the weight of yellow. What is the weight of a green melon?

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