Prealgebra

# Key Terms

PrealgebraKey Terms
circumference of a circle
The distance around a circle is called its circumference.
diameter of a circle
A diameter of a circle is a line segment that passes through a circle’s center connecting two points on the circle.
equivalent decimals
Two decimals are equivalent decimals if they convert to equivalent fractions.
mean
The mean of a set of $nn$ numbers is the arithmetic average of the numbers. The formula is $mean=sum of values in data setnmean=sum of values in data setn$
median
The median of a set of data values is the middle value.
• Half the data values are less than or equal to the median.
• Half the data values are greater than or equal to the median.
mode
The mode of a set of numbers is the number with the highest frequency.
A radius of a circle is a line segment from the center to any point on the circle.
rate
A rate compares two quantities of different units. A rate is usually written as a fraction.
ratio
A ratio compares two numbers or two quantities that are measured with the same unit. The ratio of $aa$ to $bb$ is written $aa$ to $bb$, $abab$, or $a:ba:b$.
repeating decimal
A repeating decimal is a decimal in which the last digit or group of digits repeats endlessly.
unit price
A unit price is a unit rate that gives the price of one item.
unit rate
A unit rate is a rate with denominator of 1 unit.