12) The probability that a house in an urban area will develop a leak is 5%. If 20 houses are randomly selected, what is the mean of the number of houses that developed leaks? (Special formula) A) 0.5 B) 1.5 C) 1 D) 2 13) A quiz consists of 620 true or false questions. If the student guesses on each question, what is the standard deviation of the number of correct answers, approximatelly? (Special formula) A) 17.6068169 C) 12.4498996 B) 2 D) 0
Percentage
A percentage is a number indicated as a fraction of 100. It is a dimensionless number often expressed using the symbol %.
Algebraic Expressions
In mathematics, an algebraic expression consists of constant(s), variable(s), and mathematical operators. It is made up of terms.
Numbers
Numbers are some measures used for counting. They can be compared one with another to know its position in the number line and determine which one is greater or lesser than the other.
Subtraction
Before we begin to understand the subtraction of algebraic expressions, we need to list out a few things that form the basis of algebra.
Addition
Before we begin to understand the addition of algebraic expressions, we need to list out a few things that form the basis of algebra.
12 and 13
![12) The probability that a house in an urban area will
develop a leak is 5%. If 20 houses are randomly
selected, what is the mean of the number of houses
that developed leaks? (Special formula)
A) 0.5
B) 1.5
C) 1
D) 2
13) A quiz consists of 620 true or false questions. If the
student guesses on each question, what is the
standard deviation of the number of correct
answers, approximatelly? (Special formula)
A) 17.6068169
C) 12.4498996
B) 2
D) 0](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F618f0b96-b1f5-4287-993c-e38eed778e96%2Fb81a6e5f-8507-4d29-8132-51222658bb0a%2Fjobcblk.jpeg&w=3840&q=75)
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