we are converting in to mm so we need to know the conversion factor. How many in in 1 mm. We will have to look that up. It turns out there are .03937in in every mm.
So we need to get rid of mm so we want that on the top left and bottom right
35mm .03937in
---------- x --------------
1 1mm
the mm units cancel and we can multiply to get 1.37795in
we need to round that to the nearest hundredth. Since the thousandths place is greater than 5 we round up to
1.38in