# Question #51f4c

##### 2 Answers

29

#### Explanation:

Let’s make R stand for the Red marbles, and B for the Black.

From the info given, we can see that red has twice more than black plus 3, so

Note that the

You want to replace R with the equation we found earlier, so:

And since we know the total amount of marbles, we can plug that in.

Move like terms together (subtract 3 on both sides, 2B+B = 3B)

Solve B (Divide both sides by 3)

We have solved the amount of black marbles. There are 13 black marbles!

Now plug it back to the R equation we found earlier to get the amount of red marbles. (Equation is 2B+3.) Since we found the amount of black marbles (B), you can replace B with 13 to find R

There are therefore 29 red marbles.

Pam has a total of

#### Explanation:

**Method 1**

Let the number of black marbles be

Then the number of red marbles is

By setting up an equation,

Therefore, Pam has a total of

**Method 2**

Let the number of red marbles be

Then the number of black marbles is

By setting up an equation,

Therefore, Pam has a total of