Answer:
D. 81
Step-by-step explanation:
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Here is my answer:
Number of days: 30
Mean of the data set = (68 + 70*2 +74*2 +76*4 +78 +80*5 + 82*3 +84*5 + 88 +88*3 + 92*3) /30 = 81
Answer:
3(y-4) + 3 = 9
3y -12 +3=9
3y -9 = 9
3y = 9+9
3y=18
y=18÷3
∴y=6
Step-by-step explanation: