Answer:
86
Step-by-step explanation:
Firstly,
Average = Sum/Number of Numbers
Since 7 grades' average is 77, so we can say:
77 = Sum/7
Hence, Sum = 77 * 7 = 539
Now,
81 - 18 = 63 [63 marks were recorded incorrectly. actual sum would be 63 more]
So,
Actual Sum should be 539 + 63 = 602
Actual Average = 602 / 7 = 86
Hence, actual report card average would be 86
The correct answer is 541.2 to be exact
Answer:
A good estimate for the slope is 95/60
Step-by-step explanation:
The formula to calculate the slope between two points is equal to

From the graph take the points
(0,0) and (80,125)
substitute


simplify

Multiply by 3.75 both numerator and denominator



therefore
A good estimate for the slope is 95/60