Here's how to convert 170 millimeters (mm) to inches:

* Know the conversion: 1 inch = 25.4 millimeters

* Set up a proportion: 1 inch / 25.4 mm = x inches / 170 mm

* Solve for x:

* Cross-multiply: 1 inch * 170 mm = 25.4 mm * x inches

* Simplify: 170 inches * mm = 25.4 mm * x inches

* Isolate x: x inches = (170 inches * mm) / 25.4 mm

* Calculate: x inches = 6.69 inches (approximately)

Therefore, there are approximately 6.69 inches in 170 millimeters.