this just wants us to calculate 4/5-1/3
make common denom
4/5 times 3/3=12/15
1/3 times 5/5=5/15
4/5-1/3=12/15-5/15=(12-5)/15=7/15
7/15lb is left
Answer:
3×2 + 3×-b
Step-by-step explanation:

Answer:
The test statistics is
Step-by-step explanation:
From the question we are told that
The sample size is n = 100
The null hypothesis is 
The alternative hypothesis is 
The sample mean is 
The standard deviation is 
The level of significance is 
Generally the test statistics is mathematically represented as

=> 
=>