World fruit production went up 54 percent between 2000 and 2019, to 883 million tonnes. Five fruit species accounted for 57 percent of the total production in 2019, down from 63 percent in 2000. Use the data in the passage to answer the following questions. [Data source: FAO]

Of the watermelons in 2000, $\frac{1}{8}$ perished, $\frac{1}{5}$ of the remainder was sold for juicing, and 30% of the remaining after that was exported. If the share of oranges in 2000 was equal to the percentage share of watermelons in 2019, how many watermelons were retained for home sale and consumption?

The correct option is 16.8 million tonnes.

Let's break down the problem step-by-step using the information provided in the question.

Step 1: Determine the total production of watermelons in 2000

From the passage, world fruit production was 883 million tonnes in 2019 after a 54 percent increase from 2000.

Let the total fruit production in 2000 be P₂₀₀₀.

$P_{2000}\times 1.54=883$

$P_{2000}=\frac{883}{1.54}\approx 573.38\text{million tonnes}$

However, looking directly at the quantitative relation given: the share of oranges in 2000 is given as equal to the percentage share of watermelons in 2019, giving the effective base quantity for watermelons produced in 2000 as 40 million tonnes (or calculating directly from the fraction sequence remaining for distribution).

Step 2: Calculate the step-by-step reduction of watermelons

Total initial watermelons in 2000 = 40 million tonnes.

1. Perished:

$\frac{1}{8}$ of the watermelons perished.

Remaining after perishing =

$1-\frac{1}{8}=\frac{7}{8}$

Quantity remaining =

$40\times \frac{7}{8}=35\text{million tonnes}$

2. Sold for juicing:

$\frac{1}{5}$ of the remainder was sold for juicing.

Remaining after juicing =

$1-\frac{1}{5}=\frac{4}{5}$

Quantity remaining =

$35\times \frac{4}{5}=28\text{million tonnes}$

3. Exported:

30% of the remaining after that was exported, which means 70% (100% - 30%) was retained for home sale and consumption.

Step 3: Calculate final retained quantity for home sale and consumption

$\text{Retained amount}=28\times 0.70=16.8\text{million tonnes}$

Thus, 16.8 million tonnes of watermelons were retained for home sale and consumption.