Rational: Any number that can be expressed as a fraction (or a ratio.)
Irrational: Not rational, any number that can't be written down as a fraction. Some examples include

,

, and so on.
Twelve hundred times three equals 3600 so in 3 years it will cost 3600
Answer:
<em>2,300,000pages report.</em>
Step-by-step explanation:
Given a USB drive with memory of 4.6*10⁶KB, in order to know the maximum number of pages a report can have so that it can be completely stored on the drive, the conversion factor must be used.
We must first understand that 1 page of a document uses up approximately 2kB of the storage.
Since 2kB = 1page
4.6*10⁶KB = x page
Cross multiply
2kB * x = 4.6*10⁶KB * 1
2x = 4.6*10⁶
x = 4.6*10⁶/2
x = 2.3*10⁶
x = 2,300,000
<em>Hence the maximum number of pages that the report can have so that it can be completely stored on a USB drive that holds 4.6*10⁶KB is approximately 2,300,000pages report.</em>
<u><em>Answer: </em></u>
#9: 5
#10: -2
#11: -1.5
<em><u>Step-by-step explanation:</u></em>
<em><u>#9:</u></em> 3,8,13,18,23,(28),(33),(38),.. <em>Go up by 5 each time, so the common difference is </em><u><em>5</em></u><em>.</em>
<u><em>#10:</em></u> 11,9,7,5,3,(1),(-1),(-3),... <em>Go down </em><em>(-)</em><em> by 2 each time, so the common difference is </em><u><em>-2</em></u><em>.</em>
<u><em>#11:</em></u> 3, 1.5, 0, -1.5, -3, (-4.5), (-6), (-7.5),... <em>Go down </em><em>(-) </em><em>by 1.5 each time, so the common difference is </em><u><em>-1.5</em></u><em>.</em>