The value of investments increased by 8 per year from 1 400 to EUR 2 800 euros. investment The average annual return was then 9,05 %. 2. 10,25 %. 3. 12,50 %.
+118723 I think that you may be having a problem with your translator LOL. 
I think that this is what you mean.
In 8 years the value of an investment increased from 1400 euros to 2800 euros.
Find the average annual return.
Ok if I assume this is simple interest the answer is just 100%/8=12.5%
I'll explain this.
2800=2*1400 therefore in 8 years the original amount has increased by 100%
100% divided by 8 years is an average of 12.5% each year.
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If it is compound interest the answer is more complicated.
$$\\2800=1400(1+r)^8\\\\
2=(1+r)^8\\\\
2^{0.125}-1=r\\\\
r=0.090507732\\\\
r\approx 9.05\%$$
It should really be compound interest so I would go with 9.05%
+118723 I think that you may be having a problem with your translator LOL.
I think that this is what you mean.
In 8 years the value of an investment increased from 1400 euros to 2800 euros.
Find the average annual return.
Ok if I assume this is simple interest the answer is just 100%/8=12.5%
I'll explain this.
2800=2*1400 therefore in 8 years the original amount has increased by 100%
100% divided by 8 years is an average of 12.5% each year.
----------------------------------------------------------------------------------------
If it is compound interest the answer is more complicated.
$$\\2800=1400(1+r)^8\\\\
2=(1+r)^8\\\\
2^{0.125}-1=r\\\\
r=0.090507732\\\\
r\approx 9.05\%$$
It should really be compound interest so I would go with 9.05%
