diff --git a/exercises/number_line.html b/exercises/number_line.html index f03afa8c6..1442da95d 100644 --- a/exercises/number_line.html +++ b/exercises/number_line.html @@ -1,60 +1,77 @@ - +
What number does the orange dot represent?
-What number is plural( abs( DISTANCE ), "position") to the leftright of the orange dot? The distance between adjacent tick marks is 1.
+What number does the orange dot represent?
+We know where 0
is on this number line because it is labeled.
Numbers to the right of 0
are positive, while numbers to the left of 0
are negative.
Starting from 0
, we move abs( NUMBER )
to the leftright to reach the orange dot.
Thus, the orange dot represents the number NUMBER
.
We know where MIDPOINT
is on this number line because it is labeled.
Numbers to the right of MIDPOINT
are bigger, while numbers to the left of MIDPOINT
are smaller.
We need to find the number represented by the blue dot, which is plural( abs( DISTANCE ), "position") to the leftright of the orange dot.
+Starting from MIDPOINT
, we move abs( NUMBER-MIDPOINT+DISTANCE )
to the leftright to reach the blueorange dot.
Thus, the blueorange dot represents the number NUMBER+DISTANCE
.
NUM \times 1 =
NUM
+Any real number multiplied by 1
equals itself.
Without performing any multiplication steps, we know that NUM \times 1 = NUM
.
This fact about multiplying by 1
is known as the identity property of multiplication, and it is useful for finding equivalent fractions.
NUM + 0 =
NUM
+Any real number plus 0
equals itself.
Without performing any addition steps, we know that NUM + 0 = NUM
.
This fact about adding by 0
is known as the identity property of addition.
By what number can we multiply NUM
to get 1
?
1 / NUM
+Any real number x
(except 0
) can be multipled by \dfrac{1}{x}
to get 1
.
Without performing any multiplication or division, we know that NUM \times \dfrac{1}{NUM} = 1
.
Thus, the answer is \dfrac{1}{NUM}
.
This fact about multiplying by \dfrac{1}{x}
is known as the multiplicative inverse property.
+
What number can we add to NUM
to get 0
?
-1 * NUM
+Adding the negative inverse of a number to that number equals 0
.
Without performing any addition or subtraction, we know that NUM +(-1 * NUM) = 0
.
Thus, the answer is -1 * NUM
.
This fact about adding negative inverses is known as the additive inverse property.
+