Isolating a variable in the formula - practice problems - page 3 of 145

Number of problems found: 2886

Antecedent and consequent
In a ratio which is equal to 5:8, if the antecedent is 40, then find the consequent.
Direct proportional
If m is proportional to n and m=5 when n=4, then what is the value of m when n=18?
Two circles 3
Two circles are inscribed in a square whose side is 4 cm. Find the radius of the smaller circle.
The radius 3
The radius of a solid circular cylinder decreases by 20% and its height increases by 10% . Find the percentage change its : (a) volume (b) curved surface area.
Common work
39 men can repair a road in 12 days working 5 hours a day. How many days will be required to complete the work by 30 men working 6 hours a day?
Palidrom
A number consists of two digits whose product is 24. When 18 is subtracted from the number, the digits change their places. Find the number.
Long train
A 110 m long train crosses a tree in 3 s. How long will it take to cross a 165 m long platform and 135 m long bridge, If the platform and bridge are at a distance of 30 m?
Two men 2
Two men are on opposite sides of a tower. They measure the angles of elevation of the top of the tower as 30° and 45°, respectively. If the height of the tower is 50 m, find the distance between the two men.
Square lawn
A square lawn has a 2 m wide path surrounding it. If the area of the path is 136 square meters, find the area of the lawn.
Three cubes
Three cubes of iron whose edges are 6 cm, 8 cm, and 10 cm, respectively, are melted and formed into a single cube. Find the edge of the new cube.
A town 3
A town with 12,000 people has been growing at a rate of 2.5% per year. How many years ago was the population 8,000?
An iron rod
If 22.5 meters of a uniform iron rod weighs 85.5 kg, what will the length of 22.8 kilograms of the same rod?
A sum 6
A sum at simple interest of 4% per annum amounts to 3120 USD in 5 years. Find the sum.
Move the average
If the average of 5 numbers is 20, the number which should be added to first number to make the average becomes 30?
South and then east
William walks 16 m south from his house and turns east to walk 63 m to reach his friend's house. While returning, he walks diagonally from his friend's house to reach back to his house. What distance did he walk while returning?
Average age 4
The average age of 31 people in a group is 19. If one person is reduced to 18, the average age becomes 18. Find the age of the reducing person.
Binary series
The 4th term of a G.P. is 16 and the 7th term is 128 . Find the first term and common ratio of the series.
Split 207
Split number 207 into three parts such that these are in the arithmetic progression (AP) and the product of two smaller parts is 4623.
Spheres to cone
Two solid spheres of radii 2 cm and 4 cm are melted and recast into a cone of height 8 cm. Find the radius of the cone so formed.
A mobile
A mobile phone and a tablet were sold at a profit of 10% and a loss of 8% respectively . If the cost price of the mobile is 1.5 times that of the tablet what is the overall percentage earned by selling both the articles?

Do you have unsolved math question and you need help? Ask a question, and we will try to solve it. We solve math question.