your equation should look like (75+85+81+67+91+x) ÷6 = 77 first you multiply 6 to both sides. then you subtract all your previous numbers from 462 (the product of 6 and 77) and you should end up with 63
You start off with 5 scores but you want to find the sixth score. And also you need the average to be 77. So you can set up the equation as (75+85+81+67+91+x)/6=77. Then you can solve the equation. Start by multiplying both sides by 6 so the equation looks like 75+85+81+67+91+x=462. If you take all the numbers on the left and add them together you will get 399+x=462. Finally, you subtract the 399 from both sides. This will leave you with x=63. So the answer is 63.
