Answer:
Josie will earn $13.75 Â and her brother Sean will earn $16.25
Step-by-step explanation:
Given that For every $5.50 that Josie earns, her brother earns $6.50.
Tuesday, they earned $30.00
Using the ratio and the proportional
Josie : Sean : Total
 5.5  :  6.5  :  12
  x   :   y   :  30
So, x = 5.5 * 30/12 = 13.75
And y = 6.5 *30/12 = 16.25
So, Josie will earn $13.75 Â and her brother Sean will earn $16.25