Mathematics 5 curriculum guide 2015 I table of contents acknowledgements

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MATHEMATICS 5 CURRICULUM GUIDE 2015
Specific Outcomes
DIVISION 
Suggestions for Teaching and Learning
Students will be expected to:
Number
5N2 Continued...
Achievement Indicators:
5N2.8 Describe contexts in which 
overestimating is important.
Sometimes, when estimating, it is important to overestimate. There are 
23 people, for example, and a number of cars which can seat five people 
each. How many cars are needed? No one should be left behind, so 
students should round the number of people up or find a compatible 
number higher than 23 to ensure there are enough cars to take everyone.
Using 25 people for estimating will determine that five cars will be 
needed to take everyone.
5N2.2 Determine the 
approximate solution to a given 
problem not requiring an exact 
answer.
Students should discuss other situations where an approximate answer 
is sufficient. Teachers could present a problem such as the following: 
Students have seven days to read a novel that is 264 pages long. About 
how many pages should they read per day? Why is it not necessary to 
calculate an exact answer?
The purpose of estimating is to change numbers in a problem to close 
ones which are easier to calculate mentally, or to find an answer which 
only needs to be approximate.
5N2.7 Provide a context for when 
estimation is used to: 
• make predictions
• check the reasonableness of an 
answer 
• determine approximate 
answers.
Students should be encouraged to estimate before calculating quotients 
to check the reasonableness of their answer.
Present a scenario such as: Brianna has 823 beads and she wants to use 
them all to make eight friendship bracelets. She determines that she can 
put 13 beads on each bracelet. Is her answer reasonable? Why or why 
not?
To determine the reasonableness of the answer, students should be 
encouraged to round 823 to 800 and then think, “800÷ 8 =100” so an 
answer of only 13 beads per bracelet would not be reasonable.

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