20 % = 20/100 = 1/5
1 red marble out of 5 total marbles
1 red marble and 4 not red marbles
odds in favor means number of favorable outcomes : number of unfavorable outcomes
this basically means red marbles : not red marbles
1: 4
X≈2.48207399,<span>−<span>2.14874066</span></span>
Parentheses are used to identify which numbers you should add,multiply .ect first. So If i had
12-(3+1)=x
then you would want to solve 3+1 before you subtract 12.