Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The sample size is n = 20
The sample mean is 
The standard deviation is 
Generally the standard error of the mean is mathematically represented as

=> 
=> 
Answer:
PQ = 
Step-by-step explanation:
given MQR = 60, PQR = 75
MQP = 75 -60= 15
WE KNOW THAT MQR +QRM +QMR = 180
MPQ = MQP AS ANGLE OPPOSITE TO EQUAL SIDES ARE EQUAL
THEREFORE QMR = 90 - 60 = 30
therefore PQM = 75 - 60 = 15
PM = PQ because M is the mid point
therefore PR = PM + 
PR = 

PQ = 
Here is your answer: Combine like terms: 4a+2a=6a and 8b-6b=2b Your answer is 6a+2b