a bag contains purple marbles and red marbles, 27 in total. the number of purple marbles is 9 less than 2 times the number of red marbles. how many purple marbles are there?

There are 15 purple marbles.

Step-by-step explanation:

Given:

A bag contains purple marbles and red marbles, 27 in total.

The number of purple marbles is 9 less than 2 times the number of red marbles.

Now, to find the number of purple marbles.

Let the number of red marbles be

And the number of purple marbles be

Total marbles = 27.

According to question:

⇒

⇒

Adding both sides by 9 we get:

⇒

Dividing both sides by 3 we get:

⇒

So, to get the number of purple marbles we put the value of :

Therefore, there are 15 purple marbles.                        

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