Transcript 2. Special Number

Special Numbers
Stage 4
Year 7
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Palindromic Numbers
Palindromes are numbers or words that
are the same backwards as forwards.
Examples
madam
1221
Mum
100001
Dad
12.21
1991
Hannah
11/1/11
toot
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Palindromic Words
What about?
STEP NOT ON PETS MADAM I’M ADAM
LEPERS REPEL NO LEMONS, NO MELON
DENNIS AND EDNA SINNED ROTATOR
REVIVER ABLE WAS I ERE I SAW ELBA
A MAN, A PLAN, A CANAL, PANAMA
SUMS ARE NOT SET AS A TEST ON
ERASMUS
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Palindromic Numbers
What about Number Sentences?
11
112
1113
11114
111115
1111116
11111117
111111118
=
=
=
=
=
=
=
=
1
121
12321
1234321
123454321
12345654321
1234567654321
123456787654321
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Palindromic Numbers
More Number Sentences?
110 = 1
111 = 11
112 = 121
113 = 1331
114 = 14641
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Palindromic Numbers
More Number Sentences?
A palindromic number can be generated from any
number. All you do is to continually add a number
to its reversal until you get a palindrome.
123 + 321 = 444
86
154
605
1210
+
+
+
+
68 =
451 =
506 =
0121 =
154
605
1210
1331
Now try one yourself!!!
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Square Numbers
Can be made into squares.
1
4
9
16
1x1
3x3
12 2x2 32 4x4
42
22
25
5x5
52
36
6x6
62
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Triangular Numbers
Can be made into triangles.
1
1
3
6
10
15
21
1+2+3
1+2+3+4+5
1+2 1+2+3+4
1+2+3+4+5+6
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Sum of Triangular Numbers
What type of number is the sum of
consecutive triangular numbers?
Square Numbers
1+3 3+6 6+10 10+15 15+21
4
9
16
25
36
22
42
32
52
62
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