Transcript Big Idea

Big Idea
There is more than algorithm for each of the operations
with rational numbers. Most algorithms for operations
with rational numbers use both mental math and paper
and pencil.
Essential Understanding/Question
17 -1
How can you use mental math to add multiples of 100 to a threedigit number?
Create a story with a 3 or 4 digit number that you are
joining to a 3 digit number with a zero in the tens and
the ones place.
32 + ______ = 232
496 + _____ = 996
_____ + 400 = 782
3, 429 + ______ = 3, 729
17 - 1
Describe how you used mental math to find the missing addend in one of
the problems in the middle box?
Create your own 3 or 4 digit number sentence adding
a 3-digit number that has zeros in the tens and ones
place.
Build, draw, or write to find the missing
addend using your choice of one of the
problems in the box.
Big Idea
Numbers and calculations can be approximated by numbers that
are close and easy to compute mentally. (17-2)
Essential Understanding/Question
How can you estimate sums of three-digit numbers?
How can you estimate
sums of one of the
following problems.
423+187
1,423+2, 370
(17-2)
How does estimating help you find a reasonable answer.
Explain how you estimated to find the sum.
Create a n addition word problem using an
estimation strategy.
Show two different ways to estimate the sum.
There is more than algorithm for each of the
operations with rational numbers. Most
algorithms for operations with rational numbers
use both mental math and paper and pencil.
Essential Understanding/Question
17-3
How can you model and record adding 2 three-digit
numbers?
How can you model and
record adding 2 threedigit numbers?
17 - 3
Find the sum of 2,743 and 397.
Explain why you did or did not have to regroup.
Create an addition story using 2 three-digit numbers
that requires regrouping.
Draw, build, or write an addition sentence
using 2 three-digit numbers.
Big Idea
There is more than one algorithm for each of the
operations with rational numbers. (17-4)
Essential Understanding/Question
How do you add three-digit numbers using paper and pencil?
Your Choice
369+531
1,522+478
(17-4)
Show another way to solve the problem you chose.
Explain how regrouping is used to solve this
problem.
Create a word problem using the number you chose.
Draw or write how to regroup the problem you
chose.
Big Idea
There is more than algorithm for each of the
operations with rational numbers. Most
algorithms for operations with rational numbers
use both mental math and paper and pencil.
Essential Understanding/Question
17 – 5
What strategy can you use to find the missing part?
400 + _____ = 860
460 + ______ = 930
_______ + 370 = 560
______ + 2,100 = 4, 310
17 - 5
Find the missing part of one of the problems in the box.
Explain how you solved one of the problems in the
box.
Create an addition story problem that matches one
of the number sentences in the box.
Draw, build, or write one way to solve one of
the problems in the box.
Big Idea
Numbers and calculations can be approximated by numbers that
are close and easy to compute mentally.( 17-6)
Essential Understanding/Question
How can you estimate differences of three-digit numbers.
Your Choice
769-227
3,105-1,638
(17-6)
How does estimating help you find a reasonable answer.
Explain how you estimated to find the difference.
Create a subtraction word problem using an
estimation strategy.
Show how you would estimate to find the
difference of one of the problems.