The 11 times tables.
Stg 5/E6 x/÷ Name: _________________
Well, you lucky things, it’s time for the 11 times tables! Super-duper easy. Even your
teacher can do these. Up until 11 x 9, all you have to do is write the number you see down
twice: 11 x 2 = 22 First, circle every 11th number on the 99 chart (The first one is done for
you)– see if you can spot the pattern! Also, have a go at writing in the answers to these ones:
1.
2.
3.
4.
5.
6.
7.
8.
9.
11 x 4 = ____
11 x 8 = ____
11 x 3 = ____
11 x 9 = ____
11 x 2 = ____
11 x 5 = ____
11 x 7 = ____
11 x 6 = ____
11 x 1 = ____
4 x 11 = ____
8 x 11 = ____
3 x 11 = ____
9 x 11 = ____
2 x 11 = ____
5 x 11 = ____
7 x 11 = ____
6 x 11 = ____
1 x 11 = ____
Well that was easy. We can use this when we muck about with place value too!
a.
b.
c.
d.
e.
f.
g.
h.
i.
11 x 3 = ___ so
11 x 7 = ___ so
11 x 2 = ___ so
11 x 8 = ___ so
11 x 4 = ___ so
11 x 9 = ___ so
11 x 1 = ___ so
11 x 5 = ___ so
11 x 6 = ___ so
11 x 30 = 330
11 x 70 = _____
11 x 20 = _____
11 x 80 = _____
11 x 40 = _____
11 x 90 = _____
11 x 10 = _____
11 x 50 = _____
11 x 60 = _____
110 x 3 = _____
110 x 7 = 770
110 x 2 = _____
110 x 8 = _____
110 x 4 = _____
110 x 9 = _____
110 x 1 = _____
110 x 5 = _____
110 x 6 = _____
&
&
&
&
&
&
&
&
&
11 x 300 = _______
11 x 700 = _______
11 x 200 = 2200
11 x 800 = _______
11 x 400 = _______
11 x 900 = _______
11 x 100 = _______
11 x 500 = _______
11 x 600 = _______
Alright, I get it, far too easy for you. Still, there are a few more 11s that are handy to know. See if you can
work these out by counting on 11:
Check this on your calculator:
11 x 9 = ____ + 11 more is ______ (11 x 10)
Number Eleven Pyramids
11 x 10 = ____ + 11 more is ______ (11 x 11)
11 x 11 = ____ + 11 more is ______ (11 x 12)
11 x 12 = ____ + 11 more is ______ (11 x 13)
11 x 13 = ____ + 11 more is ______ (11 x 14)
11 x 14 = ____ + 11 more is ______ (11 x 15)
11 x 1 = 11
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = _________
Did you know? - In many popular sports around the world, such as American football,
cricket, hockey, and Football (soccer), there are eleven players in each team.
Dave Moran 2015
Stg 6 x/÷
The 11 times tables.
Name: __________________
Are you serious? The elevens are so easy you don’t even have to memorise them right? Everyone knows,
you just put the number you are multiplying down twice, then violà, hey presto you’re done! For example
11 x 3 = 33, 11 x 7 = 77 and so on. It’s true, and it works because 11 = 10 + 1. It works until 11 x 9
anyway. Then 11 x 10 is in your 10 x tables, which of course is easy too (11 x 10 = 110). Then all you have
to do is memorise the two nasty ones at the end: (Actually memorising them is a good idea)
So,
11 x 10 = 110,
11 x 11 = 121, 11 x 12 = 132.
(Alright, that’s it, finished, done, let’s go home). Hold your horses there cowboy. What if I
told you that you could multiply any two digit number by 11, in your head, by the end of
this worksheet? You could impress your friends and family with your mental agility or win
fame and fortune as the human calculator!
OK, here’s a couple of tricks. Take the number that you are multiplying by 11. Say 12. (Yes. I know you
know the answer, just bear with me). All you do in your mind is karate chop the 12 apart so there’s a
space between the 1 and 2
Like this:
1 2
. Then add 1 + 2 and put the sum in the space.
There you have it. (You must be joking, that’s too cool to be true!)
OK then, try it for yourself:
1+5=_
11 x 15 = ???
Now try these ones:
1_5
a.
11 x 34 =
d.
11 x 62 =
3+4=_
3_4
6+2=_
6_2
1+2=3
132
You got 165, right? Check it on a calculator.
b.
7+2=_
11 x 72 =
e.
c.
11 x 53 =
7_2
2+7=_
11 x 27 =
2_7
5+3=_
f.
5_3
1+6=_
11 x 16 =
1_6
You can probably do some of these in your head already! Have a go:
g. 11 x 41 = _____
h. 11 x 26 = _____
i. 11 x 32 = _____
j. 11 x 43 = _____
k. 11 x 52 = _____
l. 11 x 13 = _____
m. 11 x 23 = _____
n. 11 x 22 = _____
o. 11 x 17 = _____
p. 11 x 25 = _____
q. 11 x 33 = _____
r. 11 x 62 = _____
s. 11 x 44 = _____
t. 11 x 53 = _____
u. 11 x 71 = _____
To be continued …
Dave Moran 2015
The NASA successful mission that got the first men to the Moon in 1969 was Apollo 11. Neil
Armstrong and Buzz Aldrin got to walk on the Moon, while poor old Michael Collins had to
stay behind and make tea in the orbiter.
Stg 6/E7 x/÷
The 11 times tables.
Name: ________________
…But what if the number in the middle comes to more than 9? Well, it’s much the same, but you just
carry and add the leftover. What? I’ll show you. Look at this one:
11 x 67 = ??? 1st, split it 6__7, then add 6 + 7 = 13. Then pop the 3 in the middle as usual. Lastly put the
leftover 1 in the hundreds column with the 6. 6 + 1 = 7 (hundred). Total 737
Still easy, just another little step.
Look at it this way:
A group of Giraffes is called a
‘tower’. There is no collective
noun for school principals
though. How about a ‘strap’
of principals? Maybe a
‘grump’ of teachers?
e.g.
e.g.
6 + 7 = 13
7 + 4 = 11
1
11 x 74 =
714
=
814
11s are
awesome.
Try:
5 + 6 = 11
1
Try:
7 + 8 = __
_
_
11 x 67 =
6_7
11 x 56 =
5_6
11 x 78 =
7_8
=
__7
=
____
=
____
This is very cool, now you can multiply any 2 digit number by 11! Try some:
a.
5 + 9 = __
b.
3 + 8 = __
_
d.
c.
1 + 9 = __
_
_
11 x 59 =
5_9
11 x 38 =
3_8
11 x 19 =
1_9
=
____
=
____
=
____
9 + 9 = __
e.
8 + 8 = __
_
f.
8 + 4 = __
_
_
11 x 99 =
9_9
11 x 88 =
8_8
11 x 84 =
8_4
=
____
=
____
=
____
OK, it seems like you’re ready to fly solo now. Try these:
g.
11 x 55 = _______
h. 11 x 68 = ________
i. 11 x 98 = _______
j.
11 x 95 = _______
k. 11 x 79 = ________
l. 11 x 94 = _______
m. 11 x 75 = _______
n. 11 x 46 = ________
o. 11 x 87 = _______
Well done, you are now officially a smarty-pants. The more curious among
you will be wondering now if there’s a trick to multiply 11 by any number at
all. Why yes. Yes there is. Check out this brilliant You Tube clip that explains
it: Look up: “Math trick - Multiply any number by eleven instantly!” on the
tecmath channel https://www.youtube.com/watch?v=7GRv84cRkzU
Extra for experts challenge:
See if you can figure a way
multiply a bigger number by
11. Try something like 4873
x 11 Then; challenge each
other to a maths battle!
Dave Moran 2015
An earthquake of magnitude 9.0 struck Japan on March 11, 2011, which to date has
been the most powerful to hit Japan. It resulted in a devastating tsunami which also
triggered a nuclear disaster at a coastal power plant.