B completes a work in 7 days. A alone can do it in 10 days. If both work together, the work can be completed in how many days?  Choose the correct choice from the following:	A) 3.75 days	B) 4.11 days	C) 5.11 days	D) 6.75 days	E) 7.33 days

Rationale: "1 / 7 + 1 / 10 = 17 / 70 70 / 17 = 4.11 days answer : b"
Answer: B