Winners from last weeks math problem, and the new problem of the week

Attributions: 
Solution and winners of last weeks math problem.

Ostrich Llama Count

 Raul and Esteban just started working at their uncle’s farm on the weekends. Their first task was to count the ostriches and llamas. When they reported to their uncle,

Raul said, “I counted 47 heads.”

Esteban added, “I counted 122 legs.”

“How many are ostriches? How many are llamas?” asked their uncle.

“It’s getting dark and I promised your mother I’d get you home for dinner. There’s no time to count again. You’ll have to figure out how many ostriches and how many llamas there are from that information when you get home. Can you give me a call after dinner and let me know your answer?”

How did Raul and Esteban figure out how many ostriches and how many llamas there were?