The half-life of a radioactive substance is 20 min. The approximate time interval (t2−t1) between the time t2 when 23 of it had decayed and time t1 when 13 of it had decayed (in min) is (integer only)

The half-life of a radioactive substance is 20 min. The approximate ti

1.	The half-life of a radioactive substance is 20 min. The approximate time interval (t2−t1) between the time t2 when 23 of it had decayed and time t1 when 13 of it had decayed (in min) is (integer only)
Answer» The half-life of a radioactive substance is $20 min .$ The approximate time interval $(t_{2} - t_{1})$ between the time $t_{2}$ when $\frac{2}{3}$ of it had decayed and time $t_{1}$ when $\frac{1}{3}$ of it had decayed (in $min)$ is (integer only)

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The half-life of a radioactive substance is 20 min. The approximate time interval (t2−t1) between the time t2 when 23 of it had decayed and time t1 when 13 of it had decayed (in min) is ​​​​​​(integer only)

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The half-life of a radioactive substance is 20 min. The approximate time interval (t2−t1) between the time t2 when 23 of it had decayed and time t1 when 13 of it had decayed (in min) is (integer only)