Half life of a radio-active substance is `20` minutes. The time between `20 %` and `80 %` decay will be

Half-life of a radioactive substance is 20 minutes. The time between 20% and 80% decay will be

Half-life of a radioactive substance is 20 minute. The time between 20% and 80% decay will be

The half life of a radioactive substance is 20 minutes. The time taken between 50% decay and 87.5% decay of the substance will be

The half-life of a radioactive substance is 20 minutes. The time taken between 50% decay and 87.5% decay of the substance will be

Half-life of a radioactive substance is 18 minutes. The time interval between its 20% decay and 80% decay in minutes is

The half-life of a radioactive substance is 20 min. the time taken between 50% decay and 87.5% decay of the substane will be

The half-life of a radioactive substance is 30 minutes, The time (in minutes) taken between 40 % decay and 85 % decay of the same radioactive substance is.