Solve.
-The difference of a number and 3 is the same as 39 less the number. Find the number.
A)18
B)-18
C)21
D)-21

Question

Quizplus · Accepted Answer

Let's call the number x. According to the problem, we have the equation x - 3 = 39 - x.

Adding x to both sides, we get 2x - 3 = 39.

Adding 3 to both sides, we get 2x = 42.

Dividing both sides by 2, we get x = 21.

Therefore, the solution is x = 21, which corresponds to choice C. Let's call the number we're trying to find "x". The problem tells us that "the difference of a number and 3" can be written as "x - 3". It also tells us that "39 less the number" can be written as "39 - x".

So, we can set up an equation:

x - 3 = 39 - x

Now we can solve for x:

2x - 3 = 39

2x = 42

x = 21

Therefore, the answer is Choice C, 21.

Solve. -The Difference of a Number and 3 Is the Same