Data Management Test

Hi Grade 5s,

Here is your study guide for our test on Data Management.

Make sure you know how to:


• read and answer questions about bar graphs, line graphs, and circle graphs


• find the mean from data (add all the numbers, divide by amount of numbers added)


• find the mode (which number occurs most frequently)


• create a bar graph


• create a line graph


• arrange data into intervals


• explain why a jagged line is used in a line graph


• recognize bias in two graphs


• explain what a sample is, and why a biased sample would be used


Remember, you can always post your questions here.

See you tomorrow!

-Ms. Lewis.

Equivalent Decimals

Hi Grade 5s,

Today we talked about equivalent decimals.

Remember: equivalent means equal.  If we're looking for equivalent decimals, we're looking for decimals that represent the same amount.

We looked at grids made up of 100 little squares in our text books today.  We saw that if, for example, 70 of the squares were coloured in, we could make the fraction 70/100.  We remembered from yesterday that we could turn 70/100 into a fraction: 0.70.

We noticed that we could count the squares on the grid by 1s, but we also noticed that the grid was made up of 10 rows of 10 (making 100).  If 70 squares were coloured in, we could also say that 7 rows of the 10 rows were coloured in.  We could turn that into a fraction, too: 7 out of 10 rows were coloured in, so the fraction is 7/10.  We can make this into a decimal, too: 0.7.

So...0.70 and 0.7 are equivalent decimals, because they represent the same number of squares coloured in our grid.

Hope that helps!

-Ms. Lewis.

Decimals

Hi Grade 5s,

We began our unit on decimals today.  We learned that decimals represent part of a whole number and we found examples of decimals we use everyday, like in money and in measuring with rulers.

When we talk about money, we talk about dollars and cents.  We discovered that "cent" means 100--we need 100 cents to make a dollar (just like we need 100 years to make a century).  We realised that $1.23 is a decimal number, and we can talk about it in different ways:

1 dollar and 23 cents

1 whole dollar and 23 cents towards another whole dollar

1.23

1 and 23/100  (one and twenty-three hundredths: another way to write a fraction--imagine the 23 is above the 100)

We then looked at a ruler.  If we were asked to measure 5.4 cm, we know that the 5 represents 5 whole centimetres, and the .4 represents 4 milimetres.  We need 10 milimetres to make 1 whole centimetre.  We can talk about this decimal number in different ways, too:

5 centimetres and 4 milimetres

5 whole centimetres and 4 milimetres towards another whole centimetre

5.4

5 and 4/10  (five and four tenths)

We also practised drawing decimal numbers using base ten blocks.  We began by using a hundreds flat to equal 1 whole.  Because we need 10 tens rods to make a whole, the rods represent tenths.  We need 100 unit cubes to make a whole, so the unit cubes represent hundredths.

Here's how we can show 4.62:

4 and 62/100 (four and sixty-two hundredths)

Questions? Post them here!

-Ms. Lewis

Geometry Test

TGIF, Grade 5s!

Today, I gave you your study sheets for Tuesday's test on our recent geometry unit.  Here's what the study sheet said:

We will be having a test on what we’ve been learning about whole numbers. Our test will be on Tuesday, November 24th.
Make sure you know how to:

• name triangles based on the length of their sides (e.g., equilateral, isosceles, scalene)

• name triangles based on their angles (e.g., right angle triangle, obtuse triangle, acute triangle)

• measure the angles of triangles with the use of a protractor

• draw an angle when given a measure (e.g., draw a 45° angle)

• construct a triangle given measurements of sides and/or angles (e.g., construct triangle ABC, with angle A measuring 25°, angle B measuring 80°, and the length of AB measuring 42mm)

• recognize which net creates which 3D solid

• create a net for a 3D solid (e.g., make a net for a triangular prism)

Are YOU ready?
 
Have a great weekend!
 
-Ms. Lewis.

Constructing Nets

Hi Grade 5s,


Today in class we talked about nets. Remember that to create a net, we need to find out how many faces a figure has, and what shape those faces are.
For example, I could make a net of this pentagonal prism:

First, I would count the faces and find that there are 7 faces (2 bases, 5 faces around). 5 of those faces are rectangles, and the other two faces are pentagons.

The net would look this this:

Find a solid figure around your house. See if you can figure out how you could create it with a net. Prize tomorrow for whoever posts their net here first.

Yay nets!
-Ms. Lewis.

Naming and Sorting Polygons by Angles

Happy Monday!

Today in class we began to talk about how to name triangles based on their angles.  We remembered that:

• right angles are 90°
• acute angles are less than 90°
• obtuse angles are greater than 90°

We learned that we can measure the three angles (tri-angle...remember?) of a triangle to determine whether it is a right angle triangle, an acute angle triangle, or an obtuse angle triangle.  The rule is:

• right angle triangles have one 90° angle
• acute angle triangles have all 3 angles less than 90°
• obtuse angle triangles have one angle greater than 90°

Remember: you can only have an acute triangle if all 3 angles are less than 90°.

Regular polygons are polygons (closed shape, at least 3 sides) that have all sides the same length, and all equal angles.  Irregular polygons have sides of different lengths, and different angles.

SUPER TERRIFIC BRAIN-BUSTING QUESTION:
WHAT KIND OF TRIANGLE IS A REGULAR POLYGON?  EXPLAIN YOUR ANSWER!
(First person to post the answer on the blog wins a prize in class tomorrow!)

See you tomorrow!

-Ms. Lewis.

Measuring Angles

Hi Grade 5s,


Today we began measuring angles using protractors. Don't worry if you're still trying to get the hang of it--it takes practice and patience.

I found a great interactive activity at mathisfun.com where you can use a virtual protractor to measure angles.

Try it out!

http://www.mathsisfun.com/geometry/protractor-using.html
-Ms. Lewis.