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

Number of problems found: 274

• Two thirds
Find two-thirds of the number equal to two-thirds of 99
• Circle - simple
The circumference of a circle is 198 mm. How long in mm is its diameter?
• Simple equations
Solve system of equations: 5x+3y=5 5x+7y=25
• Cross five
The figure on the picture is composed of the same squares and has a content of 45cm². What's its perimeter?
• Marriage sttus
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
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
Greg is 18 years old. He is 6 less than 4 times Bill's age. How old is Bill?
• Circle r,D
Calculate the diameter and radius of the circle if it has length 26.59 cm.
• The collector
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
Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
• Orchard
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
Determine the unknown number, which double of its fourth square is equal the fifth its square.
• Boys and girls
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
A 20 percent price increase meant a 90-crown raise. How many cost a product after?
• Clothes
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
f we add 20, we get 50% of its triple. What is this unknown number?
• Mr Duma
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
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
Rectangular floor of living room has a length 5.4 meters and a circumference 17.2 meters. What is its width?
• The parallelogram
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).