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

#### Number of problems found: 248

• Sum of four numbers The sum of four consecutive natural numbers is 114. Find them.
• Unknown number 4 I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking? Determine the radius of the circle, if its perimeter and area is the same number.
• Bike wheel The bike wheel has a radius of 30cm. How many times does it turn if we go on a 471m bike?
• Workers 9 If two workers fix two windows in an hour how many windows can 18 workers fix in the same two windows?
• Diagonal of square Calculate the side of a square when its diagonal is 10 cm.
• Raspberries Dano had 20 raspberries. John had 90% more raspberries than Dano. Determine how many raspberries have Dano and Juraj together.
• Rectangle from string String 12m. Make rectangle when one side is two times longer than its width.
• One and a half chicken One and a half chicken bears one and a half egg in one and a half day. How many eggs can withstand from 6 chicken in 6 days?
• Interior angles Calculate the interior angles of a triangle that are in the ratio 2: 3: 4.
• Cylinder twice If the radius of the cylinder increases twice, and the height is reduced twice, then the volume of the cylinder increases (how many times?):
• Thousand balls We have to create a thousand balls from a sphere with a diameter of 1 m. What will be their radius?
• VAT on books The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
• Natural gas in kWh Gas consumption for 2017 was 11,301 kWh I paid 532 € How much 1 m3?
• The volume The volume of the rotating cone is 376.8cm³, the height of this cone is 1dm. Calculate the diameter of the cone base.
• Family Son is 3/5 smaller than the mother. Mother is 99 cm higher than the son. How tall is the mother?
• Together 3 If Sally can paint a house in 4 hours, and John can paint the same house in 6 hours, how long will it take for both of them to paint the house together?
• Cube 8 The surface of the cube is 0.54 m2. Calculate the length of the cube edge.
• Four swords Obelix has three helmets, four swords and five shields. How many swords must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
• The pot The pot is a cylinder with a volume of V = 7l and an inner diameter of d = 20cm. Find its depth.

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