When solving proportions in math, the outer terms in the calculation are the extremes, and the middle terms are called the means. When setting the proportion equation a/b = c/d, the a and the d figures are the extremes. Cross multiplication to solve the equation yields a x d = b x c, and division allows for solving to identify the quantity of the variable.
Know MoreThe following word problem gives a step-by-step explanation for solving this type of proportion.
Two picnic tables are of different sizes but have proportionate dimensions. The larger table is 15 feet wide by 10 feet long, and the smaller table is 9 feet wide. What is the length of the smaller table?
The proportion sets up as follows: 15/10 = 9/x. In this problem, 15 and x are the extremes, and 9 and 10 are the means. Cross multiplying yields 15x = 90, and dividing both sides by 15 yields an answer of x = 6. Each table has a proportion of 2:3 when it comes to length:width, and the smaller table's dimensions are 3/5 those of the larger table.
Understanding how extremes and means work when solving proportion equations is one of the most important concepts to master in the early phases of algebra.
Learn more about NumbersPhi is the 21st letter of the Greek alphabet and in mathematics, it is used as a symbol for the golden ratio. The golden ratio refers to a special number that is approximately equal to 1.618. It is also known as the golden section, golden mean, divine section, medial proportion, golden cut, extreme and mean ratio, golden number or divine proportion.
Full Answer >Pi is a mathematical constant and irrational number representing the ratio of a circle's circumference to its diameter with a value of approximately 3.1416. Even though mathematicians using computers are able to calculate an approximate value for pi to 2.6 trillion digits, its exact value remains unknown. The symbol for this constant is the lowercase Greek letter pi.
Full Answer >The number notated by "e" is a famous irrational number known as Euler's number that is approximately equal to 2.72. The number "e" has no final digit and has been calculated accurately to over one trillion digits.
Full Answer >In mathematics, a prime number is any whole number greater than one that has no positive factors other than one and itself. For example, the number 17 is prime, because its only factors are one and 17.
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