Here is a pro tip! When taking 10% of anything move the decimal back ONCE. The number you get is 10% of that number. You then take that number and subtract it by your original number if you want to know how much it will cost if it was 10% off.
The reason why that works is because to take 10% of something you would need to multiply it by 0.1, which is the same as 1/10 (which is also the same as dividing the number by 10).
So you take 10% of $6.00. It's $0.60. Subtract that from your original amount.
$6.00 -$0.60
I'll let you do that one, but the answer comes out to be:
$5.40
Now to answer the question of this problem (the previous steps were if they asked for the price, but in this case you could've stopped at the 10% part)