AP EAMCET Medical 2017 Shift 1 Paper

Question : 118 of 160

Marks: +1, -0

The half-life of a radioactive isotope ‘X' is 20 years. It decays to another stable element 'Y' The number of atoms in ‘X' and ‘ Y' are found to be in the ratio 1:7 in a rock. The age of the rock is