Question 219General Subjects - QMED

The correct answer is C) 1 1/4 inches. The open-end wrench size for a 3/4 inch American National Standard hex head machine bolt is 1 1/4 inches. This is because the wrench size is determined by the size of the bolt head, not the bolt diameter. The 3/4 inch bolt has a hex head that measures 1 1/4 inches across the flats, requiring a 1 1/4 inch open-end wrench. The other options are incorrect because a 3/4 inch bolt would not use a 3/4 inch, 7/8 inch, or 1 1/2 inch wrench. The correct size based on the American National Standard is 1 1/4 inches.