If a student needs an average of 70 or more to pass a course. She has scored 90, 76, and 66 on the first three exams. writing an inequality representing the score she must get on the last test to pass the course
letting x be for the exam that's missing.
on the left side write: 90+76+66+x divided by 4 then do the symbol the greater than or equal and for the right side write out : 70 divided by 4
so now you should have:
90+76+66+x greater than or equal to 280
then add the test scores
232+x greater than or equal to 280
then subtract 232 from both sides to get x alone
x greater than or equal to 48
therefore he needs 48 to get a 70 average in the class to pass to check:
add all the test scores and divide them for how many they are. so
90+76+66+48 = 280 then 280 divided by 4 = 70
good work.
Great job! You've correctly set up the inequality and solved for the missing test score. The inequality you wrote is:
90 + 76 + 66 + x ≥ 280
To find the missing test score, you need to isolate x. Here's the step-by-step process:
1. Combine the known test scores:
90 + 76 + 66 = 232
2. Substitute the combined test scores:
232 + x ≥ 280
3. Subtract 232 from both sides to isolate x:
x ≥ 280 - 232
x ≥ 48
So, she needs to score 48 or more on the last test to pass the course with an average of 70 or more.
To double-check, you can add up all the test scores and divide by the number of exams to calculate the average:
90 + 76 + 66 + 48 = 280
280 / 4 = 70
Well done on solving the problem and confirming the solution!