In order to estimate the doubling time for a growing population, divide by the rate of growth in percentage.

To estimate the doubling time for a growing population, follow these steps:

1. Identify the rate of growth: This is usually given as a percentage. For example, if a population is growing at a rate of 2% per year, the rate of growth would be 2.

2. Divide 70 by the rate of growth: The number 70 comes from the natural logarithm of 2, which is approximately 0.693. When you divide this by the rate of growth, you get the doubling time. For example, if your rate of growth is 2%, you would do 70 ÷ 2 = 35. This means it would take approximately 35 years for the population to double.

Remember, this is an estimate. Actual doubling time can be influenced by many factors and may not follow a simple mathematical formula.