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Grade 3 – 6Topic 7 of 8
Lesson 1.7 · Comparing & Ordering Fractions9 mins read

Comparing & Ordering Fractions

Master the stick-building analogy, discover mental landmarks like half and whole, and learn how to effortlessly compare fractions without blindly memorizing rules.

🎯 The Foundation: All Ordering Rests on Unit Fractions!

Before comparing any two fractions, remember: all fractions are simply physical collections of unit fractions!

34 Proper Fraction

34 is made of 3 pieces of 14.

3 fourths shaded
1/41/41/41/4
85 Improper Fraction

85 is made of 8 pieces of 15.

8 fifths (1 whole + 3 fifths)
1/51/51/51/51/51/51/51/51/51/5
1 Whole

💡 The Value of Unit Fractions: The more equal pieces you divide a whole into, the smaller each piece becomes! (12 is huge; 110 is tiny).

🪵 1. The Stick Analogy: Building Longer Sticks!

Think of comparing fractions as gluing wooden stick segments end-to-end to see whose stick is longer. The total length depends on exactly two things:

1

Piece Length (Unit Fraction / Denominator)

How long is each individual building block? (e.g. 50 cm vs 30 cm stick pieces).

2

Piece Count (Numerator)

How many of those pieces do you place in a line?

Story from Your Notes:

Hakan (30 cm pieces) vs. Ferhunde (50 cm pieces)

Ferhunde picked 50 cm sticks. Hakan picked 30 cm sticks. Test different piece counts to see how the total stick length changes:

Ferhunde (50 cm pieces):4 pieces (200 cm)
1 piece (50 cm)6 pieces (300 cm)
Hakan (30 cm pieces):4 pieces (120 cm)
1 piece (30 cm)8 pieces (240 cm)
Ferhunde's Stick (200 cm)4 × 50 cm
50
50
50
50
Hakan's Stick (120 cm)4 × 30 cm
30
30
30
30
🏆 Ferhunde is longer by 80 cm (200 cm > 120 cm)

🎯 Two Easy Cases Emerge:

1. If piece lengths are equal: Count matters! More pieces make a longer stick.

2. If piece counts are equal: Piece size matters! Bigger pieces make a longer stick.

1️⃣ 2. Case 1: Same Denominator (Equal Unit Pieces)

When fractions share the exact same denominator, their unit pieces have the exact same length!

Example from Your Notes:
Compare58and38
58: 5 pieces of 18
5 of 8 eighthsUnit: 1/8
1/81/81/81/81/81/81/81/8
38: 3 pieces of 18
3 of 8 eighthsUnit: 1/8
1/81/81/81/81/81/81/81/8

58 > 38

Because both are made of eighths (18), having 5 pieces is physically longer than having 3 pieces!

2️⃣ 3. Case 2: Same Numerator (Equal Piece Count)

What if we take the same count of pieces, but from wholes divided differently?

Example from Your Notes:
Compare46and49

Both fractions take exactly 4 pieces. Which piece size is bigger?

16 is a whole cut into only 6 pieces (chunky, large slices).
19 is a whole cut into 9 pieces (thinner, smaller slices).

46: 4 pieces of 16 (Bigger Pieces!)
4 of 6 partsUnit: 1/6 (Large)
1/61/61/61/61/61/6
49: 4 pieces of 19 (Smaller Pieces!)
4 of 9 partsUnit: 1/9 (Small)
1/91/91/91/91/91/91/91/91/9

46 > 49

4 large pieces (16) stretch much further than 4 tiny pieces (19)!

🎯 4. Mental Strategy 1: Distance to 1 Whole (Missing Gap)

What if both denominators and numerators are different, but both fractions are just 1 piece away from 1 whole?

Case Study from Your Notes:
Compare910and56

🤔 Both fractions are missing exactly 1 piece to make a full whole! Are they equal?

No! Look at the size of the missing gap:

910 is missing:

Just 1 tiny piece of 110!

The missing gap is minuscule, so it is extremely close to 1 whole!

56 is missing:

1 larger piece of 16!

The missing gap is bigger, so it is further away from 1 whole!

9/10: Only a tiny red gap (1/10) remainsGap: 1/10 (Tiny)
1/101/101/101/101/101/101/101/101/101/10
5/6: A bigger red gap (1/6) remainsGap: 1/6 (Large)
1/61/61/61/61/61/6

910 > 56

Because 910 has a smaller missing gap to 1, it has traveled further and is closer to full!

🚀 5. Mental Strategy 2: Distance Past 1 Whole (Surplus Pieces)

Now consider the reverse: what if both fractions have passed 1 full whole by exactly 1 piece?

Case Study from Your Notes:
Compare87and109
87 Breakdown:

7 pieces make 1 whole + 1 extra piece of 17

1 whole + 1/7
1/71/71/71/71/71/71/71/71/71/71/71/71/71/7
1 Whole
109 Breakdown:

9 pieces make 1 whole + 1 extra piece of 19

1 whole + 1/9
1/91/91/91/91/91/91/91/91/91/91/91/91/91/91/91/91/91/9
1 Whole

87 > 109

Both completed 1 whole, but 87 took an extra step of 17, which is larger than 19!

🚩 6. Mental Strategy 3: Benchmarking (0, Half & Whole)

You don't always need common denominators! You can compare fractions in seconds by checking whether they are smaller or larger than Half (12) or 1 Whole.

Interactive Landmark Spectrum in Sixths (Page 8):
Slider Value:36
0/6 (0)3/6 (Half)6/6 (1 Whole)12/6 (2 Wholes)
🎯 Exactly HALF (3 is half of 6!)
Benchmarking to Half (Page 9)
Compare23and37

• In 23, half of 3 is 1.5. Since 2 > 1.5, it is greater than half!

• In 37, half of 7 is 3.5. Since 3 < 3.5, it is less than half!

23 > 12 > 37 23 > 37!
Benchmarking to 1 Whole (Page 10 & 11)
Compare129and815

129 is an improper fraction (12 > 9), so it is greater than 1!

815 is a proper fraction (8 < 15), so it is less than 1!

129 > 1 > 815 129 > 815!

⚔️ 7. When Benchmarks Fail: Too Close to Call!

What if two fractions are both slightly greater than half, and both less than 1?

The Great Showdown (Page 12):
Compare35and47

3 is slightly more than 2.5 (half of 5); 4 is slightly more than 3.5 (half of 7). Mental estimation isn't precise enough!

Method A: Equalize Unit Pieces (Denominators)

Expand both fractions so they speak the exact same unit language (135):

35(7) = 2135
47(5) = 2035

21 pieces of 1/35 > 20 pieces of 1/35! Difference is just 1/35!

Method B: Equalize Piece Counts (Numerators)

Expand both fractions so they have the exact same count of pieces (12 pieces):

35(4) = 1220
47(3) = 1221

Both have 12 pieces! Since 1/20 > 1/21, 12 larger pieces is longer!

35 > 47

Teacher's Conclusion (Page 14): Whichever method you choose, the mathematical truth is identical! Use whichever method is easiest and fastest for the numbers at hand.

🧪 8. Interactive Comparison Arena: Compare Any Two!

Select presets or build custom fractions to observe their synchronized lengths:

Quick Presets from Lesson:
35>47
Fraction A: 3/5Unit: 1/5
1/51/51/51/51/5
Fraction B: 4/7Unit: 1/7
1/71/71/71/71/71/71/7
Fraction A (35) is longer than Fraction B (47)!