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Calculating percentages
By Kate Tree (P2074) on Thursday, February 17, 2000 - 05:16 pm:

Can anyone help me?
Please- I need to calculate
70% of 8800 billion!
It's for some homework tomorrow, so please post it here soon!
Thanks

By Rachel Grant (P1159) on Thursday, February 17, 2000 - 08:18 pm:

Hi Kate! My name's Rachel and I'm 13.

To answer your question, we first need to undersdtand what it means. (Sorry if you understand this bit, I just don't know which bit you don't understand.)

We know that 8800 Billion (thats 8800,000,000,000,000) To find 10% we knock off one 0. (That's now 8800,000,000,000,00 - one less 0) To then find 70% we need to times that answer by 7.

(Hold on while I get the calculator)

Wait a sec. It doesn't fit on.....Let me think!!!!

Right. If we do 8800 x 7, then add on 11 zeros, yes?

8800
7x
-----
61600
-----

Now we add on the 11 zeros to come up with our final answer.....

6,1600,000,000,000,000 (I think)

Let me do a check.................... .................................

It's Okay, I think that's pretty right...I just got my Mum to check it - she's a maths teacher!!!

I hope this helps in time!!

Bye,

Rachel

By Richard Mycroft (P2053) on Thursday, February 17, 2000 - 11:02 pm:

8800 billion * 70% = 6160 billion
6160 billion = 6,160,000,000,000

Hope this is right
Richard

By Neil Morrison (P1462) on Friday, February 18, 2000 - 07:33 pm:

Quite literally, 'per cent' means per hundred, so 70% is 70 per 100, i.e. 70/100 = 0.7

So to find 70% of 8800 billion, multiply by 0.7. Works similarly for all percentages.

PS: was it a UK or US billion (UK is 1,000,000,000,000, US is 1,000,000,000)

By Jonathan Kirby (Pjk30) on Saturday, February 19, 2000 - 06:26 pm:

A billion is 1,000,000,000 in the UK too. It used
to have 12 zeros in the UK but it was officially
changed to be the same as the rest of the world
some time. I think that it happened quite a long
time ago, but I don't know exactly when. Perhaps
someone does?

Jonathan

By Rachel Grant (P1159) on Saturday, February 19, 2000 - 08:46 pm:

To Jonathan. Are you sure that is a billion? My Mum is a maths teacher and she wrote it down as 1,000,000,000,000 for me, I think, because a billion is a million million.
Rachel

By Richard Mycroft (P2053) on Saturday, February 19, 2000 - 09:29 pm:

In England, a billion used to be 1,000,000,000,000
However, it is now 1,000,000,000
Richard