0 Comments
80 <= (82+88+x)/3 <= 85 this is the compound inequality
multiply all sides by 3
240 <= (82+88+x) <= 255
combine like terms
240 <= (170+x )<= 255
subtract 170 from all sides
70 <= x<= 85
She must score between 70 and 85 inclusive
9.4m questions
12.2m answers