<span>twice the sum of a number and seven is 8
2(x+7)=8</span>
If you are grounded, there are two options - you are only grounded or you have extra chores too. Therefore, at that point, there is a 100% chance of you already being grounded - we need to figure what percentage of 100 the extra chores is. To find that, we can do 50/85= around 59% percent