Examples for 9th grade

Number of problems found: 2591

  • Stamps and albums
    stamp Michail has in three albums stored 170 stamps. In the first album, there are 14 more than in the second and in the second is by 1/5 less than in the third. How many stamps are in the first album?
  • Pyramid cut
    ihlan_rez We cut the regular square pyramid with a parallel plane to the two parts (see figure). The volume of the smaller pyramid is 20% of the volume of the original one. The bottom of the base of the smaller pyramid has a content of 10 cm2. Find the area of the
  • Inverted nine
    clock-night-schr In the hotel,, Inverted nine" each hotel room number is divisible by 6. How many rooms we can count with three-digit number registered by digits 1,8,7,4,9?
  • Water well
    studna Drilled well has a depth 20 meters and 0.1 meters radius. How many liters of water can fit into the well?
  • Sugars
    vaha2 In what ratio must two sorts of sugar, costing #390 and #315 per kg respectively, be mixed in order to produce a mixture worth #369 per kg?
  • Vertices of a right triangle
    right_triangle_5 Show that the points D(2,1), E(4,0), F(5,7) are vertices of a right triangle.
  • Shoes and slippers
    prezuvky Shoes were three times as many as slippers. If shoes were cheaper by 120, it would be twice as expensive as slippers. How much cost shoes and how much slippers?
  • Diagonals of diamond
    kosostvorec_4 Find the area and circumference of the diamond ABCD with 15m and 11m diagonals.
  • James
    nine James paints a fence. If every day instead of 14 planks painted 16 would be done on one day earlier. How many of planks has a fence altogether?
  • Coin and die
    die Flip a coin and then roll a six-sided die. How many possible combinations are there?
  • Pool 2
    bazen_pritok The first supply by the pool fill for five hours and the second fill for six hours, drain should be drained for 15 hours. For how many hours the pool is full, when we open both inlet now and outlet open two hours later?
  • Legs
    zidle In the room are four-legged chairs, three-legged stool, and all are sitted with (one) people. I counted all the leg room and there were a total of 39. How many are there chairs, stool and people?
  • Sales tax
    penize_49 A sales tax on a Php 10,800 appliance is Php.1,620. What is the rate of sales tax?
  • Three numbers
    trojuhelnikova_cisla What is three numbers which have the property: the sum of the reciprocals of the first and second numbers is 12/7, the first and third 11/24 and the second and the third 3/8.
  • 7 digit number
    numbers2_49 If 3c54d10 is divisible by 330, what is the sum of c and d?
  • Klara
    tourists_6 Klara and Jitka went on a hiking trip at 13 o'clock at speed 5km/h. At 14 o'clock, Tomas ride on the bike at an average speed of 28 km/h. How many hours and at what distance from the beginning of the road Tomáš caught the two girls?
  • Diagonals
    koso_uhlopricky Given a rhombus ABCD with a diagonalsl length of 8 cm and 12 cm. Calculate the side length and content of the rhombus.
  • Commitee
    committees A class consists of 6 males and 7 females. How many committees of 7 are possible if the committee must consist of 2 males and 5 females?
  • Katy MO
    reporter_saved6 Kate draw triangle ABC. Middle of AB have mark as X and the center of the side AC as Y. On the side BC wants to find the point Z such that the content area of a 4gon AXZY was greatest. What part of the triangle ABC can maximally occupy 4-gon AXZY?
  • The ship
    ship_1 The ship went upstream speed of 20 km/h in relation to water. River flows at speed 10 km/h. After half an hour, he stopped and returned downstream to the starting point. How long it took way back when even if downstream speed of ship is 20 km/h in relatio

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