Five times a number is 375. What is the number?

2 Answers
Apr 7, 2016

75.

Explanation:

So the first part of the question: "Five times a number is 375." is actually saying: "Some number multiplied by 5 is equal to 375", which looks like this:

x*5= 375

Which is the same as:

5x= 375

The second part of the problem: "What is the number?" tells us that they want us to solve for x. We can do this by dividing both sides of our equation (5x= 375) by 5, which looks like this:

5x= 375

=(5x)/5= 375/5

Lucky for us 375 is divisible by 5 (the divisibility rule for 5 states: any number is divisible by 5 if it ends in a 0 or 5) which means we will get a whole number as opposed to a fraction or decimal.

We can solve this with mental math if we remember that:

5*20= 100

and that:

5*5=25

If we add the 20 and the 5 together we get 25:

20+5= 25

Now if we multiply 25 by 5 we get 125 (This is the same as adding 100 and 25!). So this means that:

5(20+5)= (100+25)

This means that:

5*25= 125

125 just so happens to be 3 times smaller than our target number:

375/125= 3

This means that we can multiply 25 by 3 to solve for x.

25*3= 75

And there you have it! I hope that helped!

Jun 27, 2017

75 is the number and see below for the procedure!

Explanation:

Well, using algebra for these kind of problems might save you more time than guessing! So let's start, shall we?

The formula: x*5=375
Now, lets leave x on one side and also get our answer by taking 5 to the other side. We are going to do that by dividing both sides by 5! If you do something to one side, then you have to do it to the other! That will eliminate the 5 on left side and add 5 on the right side.

x*5/ 5=375/5

x=375/5
So our answer is 375/5! Wait a second... oh yes, we have one more step to do in order to finish this equation! We have to simplify it! 5 can go into 375 so you can divide that!

x=75!

There, now we have our final answer!
My source is my mind!

-Moksha