Question

A pearl is formed in one of every 10,000 oysters what percent of oysters make pearls

Answer 1

percent means parts out of 100
x%=x/100

1 in 10000
1/10000=x/100
times both sides by 100
100/10000=x
1/100=x
0.01=x

0.01% of all oysters make perls

Answer 2

if a pearl is formed in 1 of every 10,000 oysters, then it would look like this

1/10000

this is equal to 0.0001

moving the decimal point 2 points to the right, you would get

0.01%