In this lesson
One line, every rational
Every rational number (integer, fraction, decimal, signed or unsigned) has a single position on the number line. Type any rational below and the marker shows where it sits.
Fraction
38
Decimal
0.375
Equivalent fraction forms
All three forms name the same number on the line.
Interactive strip showing that negative three quarters, negative three over four, and three over negative four all name the same point on the number line.minus on the whole
minus on the numerator
minus on the denominator
As a decimal
-0.75
Comparing two rationals
To compare two numbers, place both on the line. The one further right is greater.
One positive, one negative. The positive wins, always. Even
. Every negative sits left of zero, every positive sits right.
Different forms. Rewrite one so they match. To compare
and
, turn the fraction into a decimal: −0.75 versus −0.6.
Now the order is obvious: −0.75 is further left, so it's smaller.
Fraction ↔ decimal converter
Type a fraction or a decimal — see the other form.
Two-way converter for fractions and decimals, including negative values. Type a fraction such as negative two fifths or a decimal such as negative zero point seven five and compare the equivalent form.As a fraction
As a decimal
Long division — divide the top by the bottom.
Both negative: the trap
When both numbers are negative, magnitude and order disagree.
Compare −3/4 and −2/3:
|−3/4| = 0.75and|−2/3| ≈ 0.667, so|−3/4| > |−2/3|.- But on the number line,
−2/3 ≈ −0.667sits closer to zero than−3/4 = −0.75, so−2/3 > −3/4.
The number with the larger magnitude is the smaller one when both are negative. Larger magnitude means further from zero; for negatives, further from zero means further left, which means smaller.
Ordering more than two
Same skill, repeated. Drag the cards into ascending order, smallest on the left.
Try it
Drag the cards in order — smallest on the left, largest on the right.
Drag with the mouse or finger, or focus a card and use ←/→.
Worksheet
These aren't graded. Convert to a common form when the numbers don't sit on the same scale.
Practice · Not graded
MA.7.NUM.1Practice the idea
01 / 12
Convert 3/4 to a decimal.
Convert three quarters to a decimal.Show common mistakes
Student says
“−0.5 < −0.75 because 0.5 < 0.75.”
What it reveals
Whole-number comparison logic without flipping for negatives.
Targeted response
Number Line: −0.75 sits to the LEFT of −0.5. Left = smaller. The minus sign reverses the comparison.
Student says
“To compare 7/10 and 0.65, I compared 7 and 65.”
What it reveals
Not yet integrating fraction notation as a single number.
Targeted response
Use the number line. Type 7/10, then 0.65. The marker shows 0.7 sits further right than 0.65.
Student says
“It's impossible to find a number between −2/3 and −1/2.”
What it reveals
Missing the density of rationals; thinking only of integers in the gap.
Targeted response
Number-line marker: drop a point between −0.667 and −0.5. Many points work: −0.6, −0.55, −7/12.
Going further
Density of rationals is the deeper idea: between any two distinct
rationals, infinitely many others sit. There's no "next number"
after −2/3 on the way to −1/2; you can always find one closer.
The next lesson (adding and subtracting integers) uses the same line, with arrows for the operations.