Answer: 91
Step-by-step explanation: I assume you had a typo and mean what did Ana need on the 5th quiz since you only listed 4 quiz scores.
(74 + 92 + 83 + 100 + x)/5 = 88
(349 + x)/5 = 88
((349 +x)/5) x 5 = 88 x 5
349 + x = 440
x = 440-349
x = 91
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