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Hi and welcome to another addition of hackingmaths.
Today we're going to use the ti-84plus
to find the highest common factor (otherwise known as the greatest common divisor)
and the lowest common multiple of two numbers .
The numbers that we are going to use for this calculation are 75 and 90.
Let's work out the highest common factor first.
Press MATH then scroll to the RIGHT once
Now we scroll up and we keep scrolling until you get to gcd(
Once gcd( is highlighted, like mine, press ENTER.
Now we insert the numbers.
It doesn't matter the order but I always prefer to start with the smallest
Type 75 into the calculator and then press the COMMA button.
You can find it located above the 7.
Then type 90.
If you wish you can close the brackets but it isn't necessary. Now press ENTER.
There you've worked out the highest common factor of 75 and 90.
To work out the lowest common multiple it is a very similar procedure. Press MATH.
Scroll to the RIGHT once.
Then scroll up, this time we are not looking for gcd( we are looking for lcm(.
Once lcm( is highlighted like mine, press ENTER
Type in the 75
then the COMMA button,
then 90
then press ENTER.
There you've now worked put the highest common factor and the lowest common multiple of 75 and 90.
Thanks for watching and I'll see you next time on hackingmaths.