Question

A furniture maker uses the specification 21.88 < w 13 years ago

Answer 1

\[\left| w-22 \right|<0.12\]

Answer 2

thank you :D

Answer 3

|w−δ|<ϵ
where ϵ=Tolerence
The solution to this enequality is ( similar form given in your problem)
−ϵ+δ<w<ϵ+δ
to find δ add −ϵ+δ and ϵ+δ and then divide by 2 = 22
to find ϵ subtract ϵ+δ and −ϵ+δ and then divide by 2 = 0.12
then
|w−δ|<ϵ

|w−22|<0.12