Question

If 3 times a certain number is increased by 4 the result is 28. What is the number?

If x is "the number," which of the following equations could be used to solve for the number?

3x + 4 = 28

3(x + 4) = 28

3x = 4 + 28

Answer 1

The first equation would make the most sense.

if you used the second it would not be aligned with what the original question is asking, if we expand this it would read 3x+12=28

the last equation is also incorrect, because the result of the equation would be 32 not 28.

To solve this problem just use algebra to simplify,

3x+4=28
3x=24
x=8

Answer 2

A.
`3x+4=28`

`x=8`

Explanation:

Let x be the number.

We have been given that 3 times a certain number is increased by 4.

3 times the number will be 3x and after increasing it by 4 will make our number
`3x+4`.

We are also told that the result of the above process is 28.

So we can set our given expression equal to its result as:

`3x+4=28`

Therefore, option A is the correct choice.

Let us solve for x.

`3x+4-4=28-4`

`3x=24`

`(3x)/(3)=(24)/(3)`

`x=8`

Therefore, the number is 8.