Tammy's sample may not be considered valid because, on the first hand, it is said that she only asked students from her " Math Class".
If she wants to have a survey to find out the favorite subject of the students at her school, she must conduct a survey involving all the students in her school, not just in her class. What she did is just subjective. She should use a tally listing the different subjects and compare the number of students per subject. This way, she can have an objective representation of the least liked subjects and the most liked subjects of the students on her school.
Illustrating her survey through statistics may be more reliable and valid because it shows frequencies in which she can calculate easily and accurately the percentage of the number of students per subject, in a more objective manner.
Answer: a=19
Step-by-step explanation: In order to solve this question, we must first take out the parenthesis, we can do this by taking 1/3 and multiply it by a and 5. This will give us 8=1/3a+5/3, with this we can subtract 5/3 on both sides of the equation, which will then give us, 19/3=1/3a. Last, we can divide 19/3 by 1/3 giving us 19 as our final anwser. a=19
Answer: 65h
Explanation: if the student read 65 pages per house you would multiply the hours read by 65 to determine the number of pages read :)
Answer:
Option B. 
Step-by-step explanation:
we know that
The formula to solve a quadratic equation of the form 
is equal to
in this problem we have
so
substitute in the formula
Remember that
substitute
