Question

A student was required to multiply a number by 4 and add 6 to it. Instead he added 6 to it first and then multiplied by 4. What should he do to his answer to get the correct one? If the wrong answer is 36, what is the correct one?

Answer:

If n is the number, the wrong expression is :

.

The correct expression is :

.

He needs to the wrong expression to get the correct one.

The correct answer is

.

Answer 1

The correct answer is 18

the correct expression is
`(4n+6)`

Explanation:

let the number be n

therefore if he is required to multiply n by 4 and added to 6 we have

`(4n+6)= 0-----1`

given that he did otherwise by adding 6 to n and multiply by 4 we have

`(n+6)4= 36------2`

Firstly we need to solve for n in equation 2

`4n+24= 36\\4n= 36-24\\4n= 12\\`

Dividing both sides by 4 we have

`n= (12)/(4\\)\\n= 3`

In order to solve for the correct answer let us input n=3 in equation 1 we have

`=(4n+6)= 0-------1\\=(4*3+6)= 0\\=(12+6)=0\\= 18`