Greater Than and Less Than Symbols
Date: 05/30/2000 at 09:25:07 From: Angelo Gagliano Subject: Greater/Less Than I am assisting my Middle School Son with his Math Homework. His teacher claims that '> 25' represents greater than 25. I was taught that it meant less than. The number that the angle points to was always less than and the wide angle was greater than... perhaps his teacher erred? Can you help? Thank you.
Date: 05/30/2000 at 11:27:03 From: Doctor TWE Subject: Re: Greater/Less Than Hi Angelo - thanks for writing to Dr. Math. No, the teacher is correct, > 25 would be read as "greater than 25." You are right, too, when you say "the number that the angle points to was always less than and the wide angle was greater than..." In your example, the angle 'points to' the 25, so the 25 is less than whatever, or in other words, whatever is greater than 25. Perhaps it would help if we put a number or a variable in front of the greater than sign: 50 > 25. Now we can see that the wide angle is facing the 50, the larger number. There's a mnemonic (memory aid) for remembering which way the symbol goes. Perhaps your rule is based on this or some variation. The way I learned it (with appropriate illustration) was that an alligator - which is notoriously hungry - always wants to eat the larger number. The symbol, < or > , represents its mouth, with the wide end being the open jaw. The alligator should always face the larger number. I guess you can modernize it and simplify the drawing by calling it a hungry Pac-Man instead. I hope this helps. If you have any more questions, write back. - Doctor TWE, The Math Forum http://mathforum.org/dr.math/
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