5
Choose a number from each list and subtract one from the other. Repeat for at least four pairs of numbers. What are the biggest and smallest answers you can find? A B
6
Copy each statement and work out the missing numbers. a
7
9
7+
=6
b 10 -
= 12
+ (-5) = 7
c
d (-8) -
=4
Copy each calculation and then fill in the missing numbers. a
8
8 -7 -5 3 -3 9 -8 -5 -1 4
3 + +1 = 4
b
-2 - +1 = -3
c
4 - +2 = 2
3+0=3
-2 - 0 = -2
3 - +1 = 2
3 + -1 = 2
-2 - -1 = -1
2-0=2
3 + -2 =
-2 - -2 =
1 - -1 =
3+
=
-2 -
=
0-
3+
=
-2 -
=
= -
=
Work out the answers. a
+3 - +2
b -4 - -3
f
-9 - -5
g
-6 + +6
h +6 - -7
i
k
+5 - +7
l
7 - -5
m -2 - -3 + -4
n - +1 + +1 - +2
c
+7 - -6
d -7 + -3
e
+7 - +3
-6 + -6
j
-1 + -8
These temperatures were recorded at Aberdeen Airport in January. Copy and complete the table. Draw a number line to check your answers. Sun
Mon
Tue
Maximum temperature (°C)
4
0
-1
Minimum temperature (°C)
-4
-6
Temperature (°C)
Difference (degrees)
10
Wed -7
8
8
10
Thu
Fri
Sat
2
3
5
-4
-2 6
A fish is 10 m below the surface of the water. A fish eagle is 15 m above the water. How many metres must the bird descend to catch the fish?
Challenge: Marking a maths test A A maths test consists of 20 questions. A correct answer earns 3 points, a wrong answer or missed question gets –2 points. Work out each pupil’s scores. a Aisha gets 12 right and 8 wrong. c Charles gets 8 right and 12 wrong. e What times table are all your answers in?
A computer spreadsheet is useful for this activity.
b Bill gets 10 right and 10 wrong. d Dilash gets 9 right and 11 wrong.
B What happens when a correct answer earns 4 points and a wrong answer gets –2?
1.4 Subtracting negative numbers
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