Problema Solution
To get a C in history, Nan must average 71 on four tests. Score on the first three tests were 68, 78, and 61. What is the lowest score that Nan can get on the last test and still receive a C?
Answer provided by our tutors
1) Determine goal
goal <= 71
The goal is to have a total of 4 test completed with a min average of 71, you have three test so
far so your looking to see what you the 4th test has to be
2) Determine what percent / average you have now *** almost usless step
68+78+61=207
207/3 = 69%
3) make your forumula
wanted_test_grade_(71) = 207 + b / 4
4) do some math step you never though you would use in the beginning of algebra
*use 71 becuase its your min u need
* you use the 71*4 to add the wanted percentages/points
71(4) = 207 + b / 4
71*4 = 284
284 -207 = 77
final test score needs to be atleast 77%min