The table shows the colour of the pen 200 people took during a game.

1. Find the total number of people who took a black pen.

Number who took black pens
$=15+23=38$

2. Convert the probability into a percentage.

Total number of people $=200$.

Probability as a percentage
$=\frac{38}{200}\times 100\%=19\%$

1. Identify the number of girls who took red pens and set up the probability for two selections without replacement.

From the table, the number of girls who took red pens is $5$.

Since two persons are selected at random without replacement,
$P(\text{both are girls who took red pens})=\frac{5}{200}\times\frac{4}{199}.$

2. Calculate and simplify the probability to lowest terms.

$\frac{5}{200}\times\frac{4}{199}=\frac{20}{39800}=\frac{1}{1990}.$

Correction: since $200 \times 199 = 39800$, and $5 \times 4 = 20$,
$\frac{20}{39800}=\frac{1}{1990}.$