Math practice for 13 year olds - page 334 of 428

Number of problems found: 8549

Number calculation
Determine x if 52% of x equals 9.1 * 6.
Walnuts
x walnuts were in the mission. Dano took 1/4 of the nuts, Michael took 1/8 of the rest, and John took 34 nuts. It stayed here 29 nuts. Determine the original number of nuts.
Hazelnut eating
Denis eats 12 hazelnuts in 1 day. How many more hazelnuts must he eat a day to eat 57 hazelnuts in 3 days if he ate the same amount of nuts every day?
Equation with abs
Solve this equation with absolute value member: |3(3x-1)|=8
Cone mass
The teacher brought to class two wooden models of cones, which were made of the same type of wood. The first model weighed 800g. The other had twice the base radius but half the height. Determine the mass of the second cone in grams.
Sides ratio
Calculate the circumference of a triangle with an area of 84 cm² if a:b:c = 10:17:21
Work time
Milos would do the work himself in 5 hours. How much would it take Dan to do the job together in two hours?
Number value
25% of the number x equals 2^-1. What is the value of x?
Rectangle perimeter
Determine the perimeter of the rectangle if its length and width are 2:1 and the area is 98 cm².
The rectangle
The length and width of a rectangle are in the ratio of 5:2. Its length is 7.5 cm longer than its width. Find the area of the rectangle. Determine also its length and its width.
Unknown number x
5% from an unknown number equals the number 2⁶. What is the unknown number?
Weightlifter
Weightlifter lifted 75% of its weight. Determine how much weight is lifted when he weighs 132 kg.
Shots
Determine the percentage rate of keeper interventions if 32 shots don't catch four shots.
Number calculation
12% of x is 58 more than (6²) +5. Determine x.
Painting rooms
If Daniel paints for three hours daily, he completes it in 7.5 days. How many hours a day would he have to work to finish the job 1.5 days earlier?
Square root puzzle
Peter had a number in mind and said: When I divide this unknown number by the square root of 27 and then multiply by three, I get an unknown number. What number did Peter think?
Grass
Peter and Stano lawn grass for 3 hours 12 minutes. How long would it take for Peter if Stano lawn grasses himself for 384 minutes?
Jacket price
The price of the jacket was x €. The coat was first discounted by 12% and then increased in price by 4% of the discounted amount. After discounting and subsequent price increases, the jacket cost exactly 91 euros and 52 cents. Find the flood price of the
Expression value
Specify the value of the expression: 1^-4:2^-3
Runner
Peter ran at a speed of 12.4 km/h. After 45 minutes of running, he had a hiatus. The track is 31 km long. How many kilometers is he still to run if he still runs at the same speed?

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