Help Understanding How to Knit Custom Toe-Up Socks questions

Hi. I saw this turtorial How to Knit Custom Toe-Up Socks

and i need help with understanding the 23.40 until the written stuff she does at the end.I cant seem to make out what she says for the written part and how she gets the math.:face_with_raised_eyebrow:Can any one out there make me understand it and break it down for me?:neutral_face:Any help would be nice because it really like her other videos tutorials on YouTube.:heart_eyes:

I think she is just figuring out her gauge. Stitches per inch.
She has 4.5" per inch. She needs 8.5" for the foot - 1" for negative ease. 7.5x4.5=34 stitches. She needs 10.75" for the leg -1". 9.75x4.5=44 stitches.

Hi Mike.:grinning:Could break it down more for me.What is negative ease? and how does she get 8.5 inches for the foot?
how do you get 7.5 x 4.5=34 sts?Does 1โ€™โ€™ mean add or subtract?why does she do 1โ€™'for negative ease?also how does she get the number 9.75 and 4.5?.:face_with_raised_eyebrow:Thanks.I hope that iโ€™am not bugging you with this mike.:pensive:

Ease is loose fit. Negative ease is tight fit. You want about 1" less for socks.

She wrapped a tape measure around her foot.

The math is what she did (except she says into instead of times, she does times). She needs 7.5 inches, has 4.5 stitches in an inch. 7.5x4.5, round up gets 34 stitches.

Same thing for the leg. She measured 10.75"-1=9.75 times her gauge of 4.5".

HI Mike.One more thing Could a person make it 1โ€™โ€™ inch st more if they wanted to?
Thanks Mike.

Not sure what you mean by st.
If you mean 1" positive ease. Why would you want socks will be 1" too big?