Respuesta :
Answer:
- B. 4.5/t + 4.5/(2t) = 1
Step-by-step explanation:
- Work = rate*time
- Maria's rate = 6750/t
- James's rate = 6750/2t
Their rate when working together:
- 6750/t + 6750/(2t) = 6750/4.5 ⇒
- 1/t + 1/(2t) = 1/4.5 ⇒
- 4.5/t + 4.5/(2t) = 1
Correct choice is B