Question 449738
A student's mean score on 5 tests was 84.
 The student's mean score on the first 4 of these tests was 87
 what was the student's score on the fifth of these tests? 
:
Let x = his score on the 5th test
:
{{{(4(87) + x)/5}}} = 84
4(87) + x = 5(84)
348 + x = 420
x = 420 - 348
x = 72, his score on the 5h test
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