GCD & LCD VII

8/2/2019 GCD & LCD VII

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Great Common Divisor and

Lowest Common Multiple7th Group

1. Alsyaidi Rusdi

2. Ratnah kurniati

3. Nofianti


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To make it simple, look to the

animation belowThere are two frogs: Green frog and Red frog


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Green frog

The distance of flying jump of green frog is always the same, that is about 4cubicles, and for every flying jump, it will leave their egg that will become to be

green frog too.


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Red frog

The distance of flying jump of Red frog is always the same, that is about 2cubicles, and for every flying jump, it will leave their egg that will become to be red

frog too


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There is a mouse want to cacth both ofgreen frog andred frog at the same time. So, the mouse waits theyflying jump together.


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The time when both of the frogs and can be

cacthed byMouse, at the first time is called KPK


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Green frog has flying jump about 2

And Red frog has flying jump about4

So, they will cacth at THE FIRST TIMEin4


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Because the frogs jump each about 2 cubicles and 4 cubicles so, they have thesame flying jump forTHE FIRST TIMEat 4th cubicles, So, LCD of2 and4is4


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So, for determining the LCD of two numbers or more,

we need to determine their multiple andthen findtheir first same kelipatan


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How to find GCD???


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Another way to find GCD


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LCD of 12 and 20 is

Because the blue square (12x12)

can not close over the surface of rectangle (12x20)

So, 12 is not the GCD of 12 and 20.

Because the yellow square (8x8)

can not close over the surface of rectangle

(12x20)

So, 8 is not the GCD of 12 and 20.

Because the green square (4x4)

can close over the surface of rectangle (12x20) for

the first time

So, 4 is the GCD of 12 and 20.

Because, we want to find GCD of 12 and 20,

So, we need a rectangle of 12x20 (Red).

Because the shortest side of 12 and 20 is 12.

So, we need to make a square of 12 x 12 (BLUE)

Because the length of square that is not

closed over the blue square is 20-12=8,

So, we need to make a square of 8x8 for

closing over the red rectangle

Because the length of square that is not

closed over the yellow square is 12-8=4,

So, we need to make a square of 4x4 for closing

over the red rectangle

Duplicate the green square

and try to close over

the surface of red rectangle

Obviously, all the surface of red rectangle is closed

over by green square


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From the animation above, we

conclude that GCD of 2 numbersor more is the greatest number

that divided completely the two

numbers or more.


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*If you want to find GCD or LCD in any negative

numbers, the first step is drop that negative sign and

do the term that explained before


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THANKS

Documents

GCD & LCD VII