Definition of lumbar puncture. : puncture of the subarachnoid space in the lumbar region of the spinal cord to withdraw cerebrospinal fluid or inject anesthetic drugs.
Rational Numbers A rational number is a number that can be written as a ratio. That means it can be written as a fraction, in which both the numerator (the number on top) and the denominator (the number on the bottom) are whole numbers. The number 8 is a rational number because it can be written as the fraction 8/1.
Rational Numbers. OK. A Rational Number can be written as a Ratio of two integers (ie a simple fraction). Example: 1.5 is rational, because it can be written as the ratio 3/2. Example: 7 is rational, because it can be written as the ratio 7/1.Example 0.333...xample: Ï (Pi) is a famous irrational number. Ï = 3.1415926535897932384626433832795 (and more...). You cannot write down a simple fraction that equals Pi. The popular approximation of 22/7 = 3.1428571428571... is close but not accurate. Another clue is that the decimal goes on forever without repeating.