A woodworker normally makes a certain number of parts in 24 days. But he was able to increase his productivity by 5 parts per day, and so he not only finished the job in only 22 days but also he made 80 extra parts. How many parts does the woodworker normally makes per day and how many pieces does he make in 24 days? Pick:
A) 360 B) 350 C) 340 D) 370 E) 380

Rationale: let x be the number of parts the woodworker normally makes daily . in 24 days he makes 24 ⋅ x pieces . his new daily production rate is x + 5 pieces and in 22 days he made 22 ⋅ ( x + 5 ) parts . this is 80 more than 24 ⋅ x . therefore the equation is : 24 ⋅ x + 80 = 22 ( x + 5 ) 30 = 2 x x = 15 normally he makes 15 parts a day and in 24 days he makes 15 ⋅ 24 = 360 parts . so answer is a .
Answer: A