Question

Set up an equation and solve then to find the unknown variable
'' Anil thinks of a number, if he add 5 to it and divides the sum by 2, he will get 21 '' ​

Answer 1

37

Let the number thought by Anil be x

So,

$\frac{x + 5}{2} = 21 \\ => x + 5 = 42 \\ => x = 42 - 5 \\ = > x = 37$

Therefore, the number thought by

Anil=x= 37

PLEASE MARK IT AS BRAINLIEST

Answer 2

Step-by-step explanation:

Question :

Set up an equation and solve then to find the unknown variable.

''Anil thinks of a number, if he add 5 to it and divides the sum by 2, he will get 21".

Solution :

Let's assume that the number that Anil thinks is x.

★ Case 1 :

• 5 is added to it. So, the equation becomes :

$\longrightarrow \sf \: x + 5$

★ Case 2 :

• He divides the sum by 2. So, now the equation is :

$\longrightarrow \sf \: \dfrac{x + 5}{2}$

★ Case 3 :

• This all is equal to 21.

$\longrightarrow \sf \: \dfrac{x + 5}{2} = 21$

Hence, the required equation is :

$\longrightarrow \boxed{\bf \: \dfrac{x + 5}{2} = 21}$

~Now, let's find the vale of unknown constant :

$\longrightarrow \sf \: \dfrac{x + 5}{2} = 21$

$\longrightarrow \sf \: {x + 5}= 21 \times 2$

$\longrightarrow \sf \: {x + 5}= 42$

$\longrightarrow \sf \: x= 42 - 5$

$\green{ \longrightarrow \underline{\boxed{\bf \: {x }= 37}} \: \bigstar}$

Hence, value of unknown constant (x) is 37.

Verification :

Our equation was :

$\longrightarrow \sf \: \dfrac{x + 5}{2} = 21$

Putting value of x that is 37,

$\longrightarrow \sf \: \dfrac{37+ 5}{2} = 21$

$\longrightarrow \sf \: \dfrac{42}{2} = 21$

$\longrightarrow \sf \: \cancel\dfrac{42}{2} = 21$

$\longrightarrow \underline{ \bf21 = 21}$

L.H.S. = R.H.S.

Hence, Verified!!