A sustainability club measures the amount of food waste generated on a particular day by 100 households.
The histogram shows the distribution of food waste generated by the households.
Most households generated less than 400g of food waste that day.
State one misleading feature of the histogram and explain how it could affect the reader’s interpretation of the data.[1]
Calculate an estimate of the mean mass.[1]
Calculate an estimate of the standard deviation of the masses.[1]
The club forgot to include the food waste generated by one household.
The household generated 420g of food waste that day.
The club updates the histogram to include this household and recalculates the estimated mean using the grouped data.
The club expects the estimated mean to decrease.
Without calculation, explain whether the club is correct.[1]
The club also surveys 80 households from two residential blocks, Block A and Block B.
Each household is classified according to the main type of food waste it threw away.
The frequency table summarises the data collected.
| Block A | Block B |
|---|
| Cooked Food | 22 | 29 |
| Uncooked Scraps | 17 | 12 |
Two households in Block A are chosen at random.
Find the probability that both households threw away cooked food.[2]
Three households that threw away uncooked scraps are chosen at random.
Find the probability that exactly one of the households is from Block B.[2]