To solve this question, we first need to find out the total amount that the 6 friends payed. We can do this by multiplying the amount each one of them payed by the number of friends there are. Since there are 6 friends and they each payed $10, we know that the total payed is $60.
Now, we need to find the amount that the 6 friends over-payed, which can be derived by subtracting the amount they payed and the amount they were supposed to pay.
$60 - $41.88 = =$18.12
Now that we know how much they over-payed as a group, we need to find out how much each of them over-payed individually, which will be the money they get back. This can be solved by dividing the amount they over-payed as a group by the number of friends.
$18.12 / 6 = =$3.02, meaning that they each will get back $3.02
First u need to distribute the -1 to (x + 4), creating the equation, -8 = -x - 4. Then add the -4 to both sides, and you get, -4 = -x. Then divide by -1 to both sides, and x = 4.
B is correct and C is not becasue you have to have the number multiplied by 10 to a power because then you wouldn't know what number to use as the base. I hope this helps. :)