Both, but it doesn't seem to stick. I googled for some info on the tape measure and found alot of teaching aids but very little with "how to read dial calipers".
He gets confused on dimensions like 1.33" on a print and he will set the calipers at 1.303". I show him on the calipers where 1.33" is and he gets it correct so I ask him to set them at 4.88, he sets them at 4.808". Maybe its just short term memory

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