Jerry’s average (arithmetic mean) score on the first 3 of 4 tests is 78. If Jerry wants to raise his average by 2 points, what score must he earn on the fourth test?  Choose the correct answer: A) 87 B) 89 C) 86 D) 93 E) 95
Total score on 3 tests = 78*3= 
<gadget id="calculator">78*3</gadget>
<output>234</output>
234   Jerry wants the average to be= 80   Hence total score on 4 tests should be = 80*4= 
<gadget id="calculator">80*4</gadget>
<output>320</output>
320   Score required on the fourth test= 320 - 234= 
<gadget id="calculator">320 - 234</gadget>
<output>86</output>
86   Option 86
<result>C</result>
Jerry’s average (arithmetic mean) score on the first 3 of 4 tests is 78. If Jerry wants to raise his average by 2 points, what score must he earn on the fourth test?