Final answer:
To solve the compound inequality -40<= (5/9)(F-32)<= 15 for F, we multiply all parts of the inequality by 9 to eliminate the fraction, then simplify the expression and solve for F. The solution is F<= -40 or F<= 59, so the correct option is Option 1: F<= -17.8 or F>= 139.8.
Step-by-step explanation:
To solve the compound inequality -40≤ ⅓(F-32)≤ 15 for F, we can start by multiplying all parts of the inequality by 9 to get rid of the fraction:
-360 ≤ 5(F-32) ≤ 135
We can then distribute the 5:
-360 ≤ 5F - 160 ≤ 135
Next, we can add 160 to all parts of the inequality:
-200 ≤ 5F ≤ 295
Finally, we can divide all parts of the inequality by 5:
-40 ≤ F ≤ 59
So, the solution to the compound inequality is F ≤ -40 or F ≤ 59. Therefore, the correct option is Option 1: F ≤ -17.8 or F ≥ 139.8.