Expression of a variable from the formula - 7th grade (12y) - math problems

Number of problems found: 274

  • Two thirds
    fractions_10 Find two-thirds of the number equal to two-thirds of 99
  • Circle - simple
    kruh The circumference of a circle is 198 mm. How long in mm is its diameter?
  • Simple equations
    enc2 Solve system of equations: 5x+3y=5 5x+7y=25
  • Cross five
    5squares2 The figure on the picture is composed of the same squares and has a content of 45cm². What's its perimeter?
  • Marriage sttus
    family_26 In our city, there are 3/5 of the women married to 2/3 of the men. Find what part of the population is free.
  • A fraction
    fractions_2 I think of a fraction, if we increase its numerator and denominator by one, the value of the fraction increases by one tenth, what fraction do I think?
  • Greg and Bill
    Clock0400_12 Greg is 18 years old. He is 6 less than 4 times Bill's age. How old is Bill?
  • Circle r,D
    bavlnka Calculate the diameter and radius of the circle if it has length 26.59 cm.
  • The collector
    film Harry liked to collect old movies. On 4 different days, he bought 2 movies. On 2 other days, he bought 3 movies each day. After that he sold 2 sets of 2 movies. He figured out how many he had total, and then he divided that total into 2 groups to put onto
  • Vacation
    eura_9 Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
  • Orchard
    tree_2 3/5 of the trees in the orchard are apples, 1/3 are cherries and the remaining five trees are pear. How many trees are in the orchard?
  • Unknown number
    5nums_1 Determine the unknown number, which double of its fourth square is equal the fifth its square.
  • Boys and girls
    children_16 There are 28 girls in the hall. 5/7 of all children are boys. How many children and how many boys are there?
  • Price increase
    sleva A 20 percent price increase meant a 90-crown raise. How many cost a product after?
  • Clothes
    dvojice_2 Danka and Janka collect clothes. Danka had 9 more than Janka, so she gave her 7. Which now has more cloth and how many?
  • Unknown number 24
    numbs_6 f we add 20, we get 50% of its triple. What is this unknown number?
  • Mr Duma
    garden_1 Mr Duma recently inherited a rectangular plot, part of the estate left by his late father. The plot with the following dimensions: Length=2x+1;Width=x-1. Determine the formula, in terms of x, that best describes the area of the rectangular plot. He has pl
  • Find the
    kruh Find the radius of the circular base of the vessel, whose perimeter is 2.51 m. Write the result to one decimal place in meters. Via the π sign - Ludolph's number
  • Floor
    podlaha Rectangular floor of living room has a length 5.4 meters and a circumference 17.2 meters. What is its width?
  • The parallelogram
    rovnobeznik The parallelogram has one side 2 dm long, which is one-sixth of its circumference. How many cm does the other side of the parallelogram measure?

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Expression of a variable from the formula - math problems. Examples for 7th grade (seventh).