14 students should have red hair, if that's what you're asking.
Answer:
24 months
Step-by-step explanation:
Cross-multiply
0.5 inches -------------- 1 month
12 inches ---------------- x months
0.5/12 = 1/x ===> 0.5x = 12 ===> x = 12/0.5 ===> x = 24 months
i hope this helps! let me know if you want me to explain more. sorry the picture is a little blurry
a is given to us so just plug a into the first equation:
b-3 - 3b =9
Add 3 to both sides:
b-3b=12
Combine like terms:
-2b=12
Divide by -2 to get b by itself:
b=-6
The only answer with b as -6 is the first one, (-9,-6)
Answer:

Step-by-step explanation:
From the given information:
The sample size is 28
The population mean is 24.5 (ppb)
The sample mean is 225.3 (ppb)
Thus, the null and the alternative hypothesis can be computed as:
Null hypothesis:

Alternative hypothesis:
