PR-6102UK Investigating Number Patterns 3

Eleven Times
1 2 3 4 5 6 7 8
AC C % ÷
7 8 9 x
4 5 6 –
1 2 3 =
0 . +
1 Notice what happens when the
table is extended further.
a 11 x 11 =
Do you know the pattern in
the eleven times table?
11, 22, 33, 44, 55, 66, 77, 88, 99
b 12 x 11 =
c 13 x 11 =
d 14 x 11 =
Predict the following.
a 15 x 11 =
b 16 x 11 =
c 17 x 11 =
Check your answers.
4 Try these multiplications.
a 51 x 11 =
b 27 x 11 =
c 31 x 11 =
d 34 x 11 =
e 43 x 11 =
f 72 x 11 =
2 Do you think the pattern will
continue?
Yes
3 Try some more to check.
a 18 x 11 =
b 19 x 11 =
5 What do you think you would need to
do to multiply 68 by 11?
c What happens when you reach
20 x 11?
No
To multiply any two-digit
number by 11, take the two
digits of the original number
to form the first and last digits
of the number; e.g. 42 x 11
gives 4_2. The middle digit is found by adding
these two digits; e.g. 4 + 2 = 6 answer = 462.
Viewing sample
6 Now try these multiplications.
a 59 x 11 =
b 82 x 11 =
c 77 x 11 =
d 93 x 11 =
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