2011-10-25
Totally Buble: Totally Bublé to light up North Lanarkshire
Totally Buble: Totally Bublé to light up North Lanarkshire: We're very pleased to announce that Totally Bublé will be performing at the Christmas lights 'switch-on' events in Cumbernauld and Kevin'...
Totally Buble: Totally Bublé goes LIVE
Totally Buble: Totally Bublé goes LIVE: It gives us great pleasure to announce that we have booked our first theatre shows with The Michael Bublé Tribute Band. Originating from Nor...
2008-07-16
Tip: Mental Arithmetic: Multiplying by 11
There is a quick and easy way to multiply any two digit number by 11 in your head, without the need for pen and paper. All you have to do is add the two digits of the number being multiplied and place the resultant sum in between the two digits.
This is best illustrated with an example. Say you want to multiply 63 by 11. First you would add 6 and 3, giving 9. Then put the 9 between the 6 and the 3 to give the result: 693.
There is, however, one minor catch. What if the sum of the two digits is greater than 9? Simple; just add 1 to the first digit and put the right (unit) digit of the sum in the middle. So, for 11 times 86, here's the steps you would go through in your head:
add 8 and 6, giving 14
change the 8 to a 9
put the 4 between the 9 and the 6
answer: 946.
Although this may seem a bit convoluted, that's just in the reading of the explanation. In practice, you'll be able to master this very quickly and with very little effort at all.
This is best illustrated with an example. Say you want to multiply 63 by 11. First you would add 6 and 3, giving 9. Then put the 9 between the 6 and the 3 to give the result: 693.
There is, however, one minor catch. What if the sum of the two digits is greater than 9? Simple; just add 1 to the first digit and put the right (unit) digit of the sum in the middle. So, for 11 times 86, here's the steps you would go through in your head:
add 8 and 6, giving 14
change the 8 to a 9
put the 4 between the 9 and the 6
answer: 946.
Although this may seem a bit convoluted, that's just in the reading of the explanation. In practice, you'll be able to master this very quickly and with very little effort at all.
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