How do you find the rate of change?

9 months ago


116 Replies




Vickie Shanahan

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116 Answers

Chirayu Joshi

Generally, Rate Of Change problems can solve by R = D/T, OR rate of change equals the distance traveled divided by the time it takes to do so.

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The rate of change is a way to measure how fast something is changing. To find the rate of change, we use the formula:

"rate of change = (change in y) / (change in x)"

This formula helps us to find out how much y changes for every 1 unit change in x.

For example, if we have a point A (2,4) and a point B (4,8), we can find the rate of change by using the formula.

(change in y = 8 - 4 = 4) / (change in x = 4 - 2 = 2) = 2

So, the rate of change is 2, meaning that for every 1 unit increase in x, y increases by 2 units.

This formula is especially useful when we have a graph and we want to know how steep the line is. The steepness of the line is also known as the gradient, the bigger the gradient the steeper the line, the smaller the gradient the flatter the line.

In short, the rate of change is a way to measure how much something is changing over time. It is a fundamental concept in mathematics and physics, and it is important for understanding how things change and how to model those changes.

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Ashan Dayananda

In different situations, we have to calculate rate of change. That means we have given two points in a functions and just like slope between those points. When x=a , f(a) and x=b, f(b) , then rate of change between a & b could be defined by

Rate of change =[ f(b) - f(a) ] / (b - a)


To find rate of change on a linear graph (straight line) :

1) You have to pick two points on the line

2) Measure the distance in the y axis and the distance in the x axis between the points (you can sketch a right triangle under the points to make this easier)

3) Put the values you got into the formula: change in y divided by change in x

Ajit Kumar

Rate of Change is a general concept and it is applied in various subjects like Maths and Science. Let's understand it by taking an example.

In Time T, I reached from D1 to D2. What is the Rate of change.

So for this, Let's calculate

the Change in Distance= D2-D1

time taken = T

So, Rate of Change = (D2-D1)/ T

i.e change in distance per unit time. This is Rate of change.


The rate of change = change in y over change in x , if you are given 2 coordinates e.g (2,0) (3,3) and you want to find the rate of change. You would simply do 3-0 / 3-1 which would give you 3/2. This will give you a gradient y=3/2x + c. To find c you would simply sub one of the coordinates back in to this equation.

Aishwarya Bandaru

The rate of change is also known as the gradient or slope.

Rate of change = (change in quantity 1) / (change in quantity 2)

Given 2 points (x1, y1) and (x2, y2), the rate of change between them is:

Δy / Δx = (y2 - y1) / (x2 - x1)

Michail Lazos

The rate of change is difference of y divided by difference of x. In other words it is the derivative at a given point.

George Asquith

The rate of change is how much one quantity changes per unit of another amount. Normally this is how much y changes for every set amount that x increases or decreases. This is the same as the gradient (in straight lines gradient is fixed and is shown as m in y=mx+c, in other graphs, the gradient changes). This can be calculated by having two points each with x and y coordinates. y1-y2 divded by x1-x2.

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if you are given a graph then draw a tangent as accurately as you can(doesn't matter if its perfect) and use change in y divided by change in x for your straight line to get the gradient which is the rate of change. just watch your units it will ber per second or per minute, something like that depending on the experiment

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Archita Sinha

The rate of change on a line graph is called the gradient and is calculated by the change in y axis/ change in x axis. What this means is that you find 2 points on the line and find the difference between the y coordinates and divide that by the difference in x axis.

Soumyadeep Mukherjee

Rate of change of any property is given by the change in the value of property per unit time. For example if the temperature at a location drops 5°C in 5 minutes. Then the rate of temperature is 5/5 °C/min i.e. 1 °C/min

Holly Willis

change in y over the change in x

Santosh Rimal

we can find through gradient in graph or by calculation of numbers

Faizan Ahmed

For a linear set of values the rate of change will be the change in y-values divided by the change in x-values in other words the gradient of a straight line. In the set of values relating to a curved line the rate of change on each point can be found by differentiating the equation of that curve and using the values of x of the point you need to find the rate of change at.

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