19 Blogs of Maths (Mathematics)

Problems on Ages (Quick Tips and Tricks) 1) If the current age of a person be X, then - age after n years = X + n - age n years ago = X – n - n times the age = nX - If ages in the numerical are mentioned in ratio A : B, then A : B will be AX and BX 2) If sum of ages...

For Practive use this Exercise https://gyangossip.com/average-test-part-1/mock-test/T12405

1. Numeral : In Hindu Arabic system, we use ten symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, called digits to represent any numbers. A group of digits, denoting a number is called a numeral. We represent a number, say 689745132 as shown below : We read it as : ‘Sixty- eight crores,...

The Chain Rule is a formula for computing the derivative of the composition of two or more functions. For instance, if f and g are functions, then the chain rule expresses the derivative of their composition. The Chain Rule Formula is as follows – dy/dx = dy/du * du/dx ...

Time and Work involves dealing with the rate at which individuals or group of people work. Conventionally we start by assuming the number of days (T) taken by a single person to complete a certain task where the rate of work of the person, or the amount of work the person can do in one day, is ...

The problems of pipes and cisterns usually have two kinds of pipes, Inlet pipe and Outlet pipe / Leak. Inlet : A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet. Outlet : A pipe connected with a tank or a cistern or a reservoir, emptyi...

1. Basics Speed = Distance / Time Time = Distance / Speed Distance = (Speed × Time) 2. Convert kilometres per hour(km/hr) to metres per second(m/s) x km/hr = x * 5/18 m/sec 3. Convert metres per second(m/s) to kilometres per hour(km/hr) x m/sec = x * 18...

1. a km / hr = (a * 5/18) m/s. 2. a m / s = (a * 18/5) km / hr. 3. Time taken by a train of length / meters to pass a pole or a standing man or a signal post is equal to the time taken by the train to cover 1 meters. 4. Time taken by a train of length / meters to pass a stationary obje...

1. In water, the direction along the stream is called downstream. And the direction against the stream is called upstream. 2. Let the speed of a boat in still water be u km/hr and the speed of the stream be v km/hr, then Speed downstream = (u + v) km/hr ...