A student scored 75, 85, and 93 on three algebra tests. What must he score on the fourth test in order to have an average grade of at least 85?

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Answer 1 · 2016-10-24T02:39:17

#87#

Let the score of the fourth test be #=x#,

#=> (75+85+93+x)/4=85#

#=> 253+x=85xx4#
#=> x=340-253=87#

Hence, the student must score at least 87 marks on the fourth test.

Answer 2 · 2016-10-24T02:45:45

87 or more

#(75+85+93+x)/4>=85#

#(253+x)/4*4 >=85*4#

#253 + x >= 340#

#x >= 340-253#

#x>= 87#