Transcript Everyday Mathematics Partial-Differences Subtraction Partial-Differences Subtraction Partial-differences subtraction involves: • Thinking about numbers in expanded notation; • Using place value to determine partial differences; and •

Everyday
Mathematics
Partial-Differences Subtraction
Partial-Differences Subtraction
Partial-differences subtraction involves:
• Thinking about numbers in expanded notation;
• Using place value to determine partial differences; and
• Adding partial differences.
Everyday Mathematic
Partial-Differences Subtraction
Solve: 471 – 293
We begin by thinking about each
number in expanded notation.
471
– 293
471 = 400 + 70 + 1
293 = 200 + 90 + 3
We can subtract in any placevalue order.
Everyday Mathematic
Partial-Differences Subtraction
Solve: 471 – 293
Let’s start with the hundreds
place.
471 = 400 + 70 + 1
471
– 293
400 – 200 = 200
293 = 200 + 90 + 3
Everyday Mathematic
Partial-Differences Subtraction
Solve: 471 – 293
Now we subtract the tens.
471 = 400 + 70 + 1
293 = 200 + 90 + 3
471
– 293
400 – 200 = 200
70 – 90 = –20
Since we are subtracting a larger
number from a smaller number,
the difference is negative.
Everyday Mathematic
Partial-Differences Subtraction
Solve: 471 – 293
Finally, we subtract the ones.
471 = 400 + 70 + 1
293 = 200 + 90 + 3
Since we are subtracting a larger
number from a smaller number,
the difference is negative.
471
– 293
400 – 200 = 200
70 – 90 = –20
1 – 3 = –2
Everyday Mathematic
Partial-Differences Subtraction
Solve: 471 – 293
We add the partial-differences
to find the total.
471 – 293 = 178
471
– 293
200
–20
+ –2
178
Everyday Mathematic
Partial-Differences Subtraction
When children use partial-differences subtraction they practice
a variety of skills related to number sense and algebraic
reasoning. For example:
• Thinking about numbers in expanded notation;
• Using place value to determine partial differences; and
• Adding positive and negative numbers.
If children start with the largest place value, which is generally
their inclination, they begin the problem-solving process with a
reasonable estimate of what the final answer should be.
Everyday Mathematic