Question

Three persons can build a wall in 4 days, then 4 persons can build it in​

Answer 1

Answer:

3 days because they work

Answer 2

Hi friend The answer is given below  ,

$\big\langle\Big\langle\bigg\langle\Bigg\langle\LARGE\;\underbrace{\underline{\sf{Understanding \;the\; question}}}\big\rangle\Big\rangle\bigg\rangle\Bigg\rangle$

Here is concept that an inverse function is a function that undoes the action of the another function. A function g is the inverse of a function f if whenever y=f(x) then x=g(y). In other words, applying f and then g is the same thing as doing nothing. We can write this in terms of the composition of f and g as g(f(x))=x.

Let's do it !!

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★ How can we find Inverse equation :

First, replace f(x) with y .

Replace every x with a y and replace every y with an x .

Solve the equation from Step 2 for y .

Replace y with f−1(x) f − 1 ( x ) .

Verify your work by checking that (f∘f−1)(x)=x ( f ∘ f − 1 ) ( x ) = x and (f−1∘f)(x)=x ( f − 1 ∘ f ) ( x ) = x are both true.

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★ Solution :-

Take the days taken x

3*4=4*x

12=4x

12/4=x

3=x

x=3 days.

4 people can do a work in 3 days

3 days

I am pretty sure it will help you in equation