Maths Help- KS3
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Maths Help- KS3
Hello all,
Any help much appreciated!
Question-
The yearly change in the yield of one particular crop in our area over the past 2 years was 20% increase followed by 20% decrease. What is the total percentage change over two years?
Thanks,
Any help much appreciated!
Question-
The yearly change in the yield of one particular crop in our area over the past 2 years was 20% increase followed by 20% decrease. What is the total percentage change over two years?
Thanks,
Re: Maths Help- KS3
Start with 100.
20% increase in year 1 gives you 120.
20% decrease is year 2 gives you a decrease of 24, so net result of 96.
In maths terms, I would describe the change as (1+.2)*(1-.2)=.96, so a total chance of 1-.96= a reduction by 4%
20% increase in year 1 gives you 120.
20% decrease is year 2 gives you a decrease of 24, so net result of 96.
In maths terms, I would describe the change as (1+.2)*(1-.2)=.96, so a total chance of 1-.96= a reduction by 4%
Re: Maths Help- KS3
Thankyou Lady muck! great... the choice answers were
-4%, -1% , 0% , 1% and 4%.
-4%, -1% , 0% , 1% and 4%.