Thirty women were examined in a hospital by a doctor and the number of heart beats per minute were recorded and summarised as follows. Find the mean heart beats per minute for these women, choosing a suitable method.

Explanation

To find the mean heart beats per minute for the 30 women examined, we will follow these steps:

### Step 1: Organize the Data
We need to summarize the given data in a frequency distribution table. The intervals (number of heartbeats per minute) and their corresponding frequencies (number of women) are as follows:

| Heartbeat Range (min) | Frequency (Number of Women) |
|-----------------------|-----------------------------|
| 65 - 68 | 2 |
...