Answer: $899
Step-by-step explanation: I subtracted $699 from $1598 so it would look like this
$1598-$699=$899
Answer:

Step-by-step explanation:
you can divide both sides by 2.35 to get the right side to be 1:

Take the numbers to one side
77(7) = 539, the total points of all her tests
539 - 18 + 81 = correct total points = 602
602/7 = 86 which is the new average