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