algebra. i plug in the numbers but it doestn seem correct.

Question

 Students in a math class took a final exam (with a grade scale of 0 to 100] and then took equivalent forms of the exam at monthly intervals thereafter. The average grade g after t months was found to be given by the function g(t) = 76 - 5-6 ln(t+1), t > 0. (Note that In; refers to the natural log function} [explanation optional) Using the model, (a) What was the average grade when the students initially took the exam, when t = 0? (b) What was the average grade on the exam when taken 4 months later, to the nearest integer

Answer 1

g(0) = 76-5 -6ln(0+1) = 76-5 -6ln1 = 76-5 - 0 = 71

g(4) = 76-5 - 6ln(4+1) = 71 - 6(ln5) = about 71-6(1.609)

=about 61.34

= about 61

the function g(t) =76-5-6ln(t+1) might have a typo?

maybe 76-5.6ln(t+1)? If so, then 67 after 4 months