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Question
The rainfall (in mm) in a city on 7 days of a certain week is recorded as follows:
| Day: | Mon | Tue | Wed | Thus | Fri | Sat | Sun |
| Rainfall (in mm): | 0.5 | 2.7 | 2.6 | 0.5 | 2 | 5.8 | 1.5 |
Find the total and average (mean) rainfall for the week.
Solution
Step 1: Finding total rainfall for the week
The rainfall in a city on 7 days
= 0.5, 2.7, 2.6, 0.5, 2, 5.8, 1.5
Total rainfall = 0.5+ 2.7+ 2.6+ 0.5+ 2+5.8+ 1.5
= 15.6 mm
Hence, total rainfall for the week = 15.6 mm.
Step 2: Finding average rainfall for the week
∴ Average rainfall(mean) = `"total rainfall"/"Number of observations"`
` = 15.6/7`
=2.23mm
hence, the average rainfall for the week is approximately 2.23 mm.
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