The right answer is 60-80% of your max. heart rate.
To properly locate your heart rate in the norms of moderate excercise: First, calculate your maximum heart rate in beats per minute. To do this, subtract your age from 220. A young adult will arrive around 200, while a senior will turn around 170. Moderate activity then corresponds to 70% to 85% of this maximum rate (or between 50 and 70 , this varies between learned societies), ie 100 to 140 beats per minute for a young person, and 85 to 119 beats per minute for a fiftieth birthday.
To check if you are in these averages, you can have a heart monitor that is usually worn in the chest and that measures the pulse permanently, or do it from time to time by putting your fingers on the veins of your wrist or your neck. Count the number of beats for thirty seconds and multiply by two.