There are 81 red, blue and yellow
counters in total.
There are 9 more red counters
than yellow ones.
There are the same amount of
yellow and blue counters.
How many of each colour are
there?

Step-by-step explanation:

Here Given

Total counters = 81

red counters are 9 more than the yellow ones.

And Yellow counter = blue counter

So let the Yellow counter be x and as blue counter and yellow counter are same then blue counter will be also x

And by the question

Red counter = 9 + x

Now

9 + x + x + x = 81

9 + 3x = 81

3x = 81 - 9

3x = 72

x = 72 / 3

Therefore x = 24

Now

Red counters = 9 + 24 = 33

Blue counters = 24

Yellow counters = 24

Hope it helped :)