Radioactive material

A radioactive material loses 10% of its mass each year. What proportion will be left there after n=6 years?

Result

x =  0.531

Solution:

n=6 p=10 %  q=1−p/100=1−10/100=910=0.9  x=qn=0.96≐0.5314≐0.531n=6 \ \\ p=10 \ \% \ \\ \ \\ q=1 - p/100=1 - 10/100=\dfrac{ 9 }{ 10 }=0.9 \ \\ \ \\ x=q^{ n }=0.9^{ 6 } \doteq 0.5314 \doteq 0.531

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