GenX-Education
  • 3 months ago
Transcript
00:00Hey kids, thanks for joining me today. I have a little story to tell you about why I need
00:06to learn about area.
00:10You see that floor and how nice it looked? Well, I thought so too, so I told my friends
00:15we should drop some bouncy balls on it to see how high they bounce. My friends thought
00:20I said bowling balls.
00:22Oh no, look what happened when they dropped bowling balls. Obviously we need to replace
00:31the floor, but in order to do that we need to learn about area. Can you help me?
00:38Great, let's take a look at some floor tiles. Once we learn about area we can figure out
00:43how to get the right amount of floor tiles to fix the room.
00:48The first thing we need to know about area is that we are only working with two dimensional
00:52shapes. What that means is we are only concerned about the width and the length. We are not
01:00worrying about how thick this tile is because we only need to know the measurement of the
01:04area to determine how many tiles we will need. Area is the space within a closed shape like
01:10this square.
01:12The second thing we need to know is what a square unit is. This square measures one
01:18centimetre by one centimetre. We can say the area of this square is one square centimetre
01:25because its measurement is one centimetre by one centimetre. The word centimetre is
01:31just a unit of measurement. We can also use other units of measurements like metres, feet,
01:37miles, well you get the idea.
01:41Here we have a rectangle that is divided into square units. The rectangle is two units
01:46wide. The length is three units. So we know the width and length but we need to find the
01:53total area of this rectangle. One thing we can do is count each square unit. We have
02:00one, two, three, four, five, six. The total area of the rectangle is six square units.
02:10Great job! Because this rectangle is divided perfectly into square units we could count
02:15the square units to find the total area. That is cool but there is an easier way to find
02:20the area. In order to find the area of any square or rectangle you can multiply the length
02:26times the width.
02:29This is called a formula. A formula is a mathematical way to solve a problem. To find the area of
02:35a square or rectangle the formula is area is equal to the length times the width. We
02:42just found the area of this rectangle by counting the square units. We got six square units.
02:48What if we plug the numbers into this formula? The area of the rectangle is equal to three
02:55multiplied by two. What is three times two? Six! Amazing! We just found the area of the
03:04rectangle without even counting the square units. This is very helpful because watch
03:09this next rectangle.
03:14Here is a rectangle that does not have lines showing us where the square units are. We
03:18could try and draw them because we know there are seven square units for the length and
03:22four square units for the width. But we are going to use the formula. Area equals length
03:27of seven multiplied by width of four. What is seven times four? The answer is twenty
03:38eight. Seven times four is twenty eight. So the answer is twenty eight square units. Awesome
03:45job guys!
03:47Now that we know how to find the area of a square or rectangle we need to find out how
03:51many tiles are needed to repair the floor in the room we just broke.
03:56Here is the room we need to know the area in square units to replace it with new floor
04:00tiles. To find the area of this room we need to find the length and the width. What is
04:06the length? Counting the square units across we get seven. What is the width? Counting
04:18down we get five. We have what we need to find the area. Area equals length which is
04:24seven square units multiplied by the width which is five square units. What is seven
04:30times five? The answer is thirty five. The area of this room is thirty five square units.
04:39Great job! Now we know how many square tiles to buy. Thirty five.
04:45Thank you so much for helping me find the area of the floor. Next time I will have to
04:49be more clear when I speak so my friends don't go throwing bowling balls. Looks like
04:55they found the bouncy balls.