Curriculum›4A›Chapter 1

Number Patterns

4A · Chapter 1 · Lesson 3 · MATH-4A-C01-L03

Learning goal. Infer, extend and justify integer sequences based on consistent increments, decrements and place-value changes.

Before you begin

Recall: Grade 3: four-digit place value, regrouping, comparison and rounding; Numbers to 1,000,000. Try these three warm-up problems. If they are difficult, revisit the prerequisite lesson before advancing.

Question 1 · calculation

From 327,627 add 3 groups of 1,000.

Show answer & reasoning
330,627

3 groups of 1,000 are 3,000; then add to the starting value.

Question 2 · calculation

In 597,513, what is the value of the digit in the hundred-thousands place?

Show answer & reasoning
500,000

The digit 5 represents 5 groups of 100,000, or 500,000.

Question 3 · representation

Write 172,606 as a number of whole thousands and remaining ones.

Show answer & reasoning
172 thousands and 606 ones

172 × 1,000 + 606 = 172,606. This grouping preserves the original value.

Key vocabulary

place value
value determined by a digit position
expanded form
sum of each nonzero place value
benchmark
nearby convenient multiple
midpoint
number exactly halfway between two bounds

Understand the concept

Number patterns depend on a rule that fits every neighboring pair. A sequence such as 120,000; 125,000; 130,000 is growing by 5,000 each time. Test a proposed rule against every step, not merely the first. Some patterns alternate rules, but such a pattern must say or show that structure clearly.

100,000← ×1010,000← ×101,000← ×10100← ×1010← ×101ones

Model it: open number line and uniform jumps. Explain what every part of the model represents, then write a matching equation.

Fully worked examples

Read the problem first and predict the answer. Then study how each quantity is represented and calculated.

Worked example 1

Question 1 · pattern

Extend this pattern: 438,594, 438,694, 438,794, ___.

Answer: 438,894

Each term increases by 100; add that step once more.

Check your understanding 1

Question 1 · pattern

Extend this pattern: 212,432, 212,682, 212,932, ___.

Show answer & reasoning
213,182

Each term increases by 250; add that step once more.

Worked example 2

Question 2 · pattern

Extend this pattern: 953,795, 953,845, 953,895, ___.

Answer: 953,945

Each term increases by 50; add that step once more.

Check your understanding 2

Question 2 · pattern

Extend this pattern: 246,697, 251,697, 256,697, ___.

Show answer & reasoning
261,697

Each term increases by 5,000; add that step once more.

Worked example 3

Question 3 · pattern

Extend this pattern: 305,969, 310,969, 315,969, ___.

Answer: 320,969

Each term increases by 5,000; add that step once more.

Check your understanding 3

Question 3 · pattern

Extend this pattern: 809,303, 809,553, 809,803, ___.

Show answer & reasoning
810,053

Each term increases by 250; add that step once more.

Guided practice

Question 1 · pattern

Extend this pattern: 547,934, 548,934, 549,934, ___.

Show answer & reasoning
550,934

Each term increases by 1,000; add that step once more.

Question 2 · pattern

Extend this pattern: 139,609, 140,609, 141,609, ___.

Show answer & reasoning
142,609

Each term increases by 1,000; add that step once more.

Question 3 · pattern

Extend this pattern: 709,996, 710,996, 711,996, ___.

Show answer & reasoning
712,996

Each term increases by 1,000; add that step once more.

Question 4 · pattern

Identify the rule for 538,232, 538,182, 538,132.

Show answer & reasoning
subtract 50

The difference between adjacent terms is consistently −50.

Question 5 · application

A sequence begins at 103,763 and increases by 50 each time. What is its fifth term?

Show answer & reasoning
103,963

The fifth term is four equal steps after the first: 103,763 + 4 × 50.

Independent practice

Question 1 · pattern

Extend this pattern: 451,533, 456,533, 461,533, ___.

Show answer & reasoning
466,533

Each term increases by 5,000; add that step once more.

Question 2 · pattern

Extend this pattern: 759,019, 759,269, 759,519, ___.

Show answer & reasoning
759,769

Each term increases by 250; add that step once more.

Question 3 · pattern

Identify the rule for 970,122, 965,122, 960,122.

Show answer & reasoning
subtract 5,000

The difference between adjacent terms is consistently −5,000.

Question 4 · application

A sequence begins at 710,753 and increases by 250 each time. What is its fifth term?

Show answer & reasoning
711,753

The fifth term is four equal steps after the first: 710,753 + 4 × 250.

Question 5 · reasoning

Maya says a pattern 119,716, 119,816, 120,016 grows by the same amount every time. Is she right?

Show answer & reasoning
No

The differences are 100 and 200, so the step is not constant.

Question 6 · pattern

Extend this pattern: 391,945, 391,995, 392,045, ___.

Show answer & reasoning
392,095

Each term increases by 50; add that step once more.

Question 7 · pattern

Extend this pattern: 852,099, 853,099, 854,099, ___.

Show answer & reasoning
855,099

Each term increases by 1,000; add that step once more.

Question 8 · pattern

Extend this pattern: 134,487, 134,737, 134,987, ___.

Show answer & reasoning
135,237

Each term increases by 250; add that step once more.

Challenge and transfer

Explain the relationships and justify your method. Multiple correct approaches may be accepted if the reasoning is valid.

Question 1 · error analysis

A student predicts 7,776 after the pattern 6,776, 7,026, 7,276. Explain and give the correct next term.

Show answer & reasoning
7,526

Adjacent terms each differ by 250; add it once to 7,276.

Question 2 · pattern

Extend this pattern: 305,512, 305,612, 305,712, ___.

Show answer & reasoning
305,812

Each term increases by 100; add that step once more.

Exit check

Question 1 · pattern

Identify the rule for 687,836, 687,786, 687,736.

Show answer & reasoning
subtract 50

The difference between adjacent terms is consistently −50.

Question 2 · application

A sequence begins at 404,794 and increases by 1,000 each time. What is its fifth term?

Show answer & reasoning
408,794

The fifth term is four equal steps after the first: 404,794 + 4 × 1,000.

Question 3 · reasoning

Maya says a pattern 478,406, 483,406, 493,406 grows by the same amount every time. Is she right?

Show answer & reasoning
No

The differences are 5,000 and 10,000, so the step is not constant.

Self-check: Revisit any item you cannot explain without looking at the answer. Return later and solve a fresh version to confirm retention.