Answer
If there is 100g of the original isotope, then after one half-life there, is 50g left and after the second half-life, there is 25g left. If 0.75 of the next half life goes through, then there will be 4.7g of decay leaving about 7.5% of the original isotope.
Work Step by Step
If there is 100g of the original isotope, then after one half-life there, is 50g left and after the second half-life, there is 25g left. If 0.75 of the next half life goes through, then there will be 4.7g of decay leaving about 7.5% of the original isotope.
