A rational number is simply a term that can be expressed as a fraction. Otherwise, that is an irrational number. So, you can use a calculator to verify if the number is rational or not.
The key characteristic of an irrational number is when it contains a long line of decimal places. For example, the term π and the Euler's number e are irrational numbers. The exact values of π and e are 3.14159 and <span>2.71828182846, respectively. In reality, those decimal places go on a long way. Particularly, </span>π<span> has a total of 2.7 trillion digits. Numbers inside radicals or roots can also be irrational numbers. For example </span>√3 is irrational because it is equal to 1.732050808. However, not all radicals are irrational. For example √15.3664 is equal to 98/25 or 3.92. That is a rational number. So, therefore, use the calculator to know the exact value of the term to properly distinguish rational from irrational.
Over which interval(s) is the function decreasing?
Let x = the numbers of girls
thus
the numbers of boys = 2x
x + 2x = 27
3x = 27
x = 9
2x = 2 . 9 =18
girls = 9 & boys = 18
= 16 * 10^13
which in scientific notation is 1.6 * 10^14
48(miles/hour)*(1 mi/5280 ft)(1 hour/60 min)
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= (48*1*1)/(1*5280*60)(ft/min)