Please Helpppppppp

Question

Eric has scores of 72​, 81​, and 86 on his history tests. Use an inequality to find the scores he can make on his final exam to receive a B in the class. The final exam counts as two ​tests, and a B is received if the final course average is greater than or equal to 80.

Answer 1

If the final counts as two tests, then there will be 5 tests total.

He has to make at least an 80 on average, so an inequality would be:

(72 + 81 + 86 + x + x) / 5 ≥ 80

which becomes

(239 + 2x)/5 ≥ 80

Answer 2

Assuming that all tests have equal weight on the grade, you can use the formula for finding an average to solve this. Remember that to find an average, you add all data values together, then divide the sum by the total number of data values. In this case, remember that while only 3 data values are given, there are actually 4 total values (one unknown).

Your inequality should look like (72+81+86+X)/4≥80.

Remember to add the numbers inside the () first, then multiply 4 on both sides, before finishing.