(a) GST amount = $1,100 / 11 = $100
(b) GST-exclusive price = $1,100 - $100 = $1,000

Working: At a 10% GST rate, the GST component of a GST-inclusive price is 1/11th of the total. $1,100 x (1/11) = $100 GST. Subtracting the GST from the total gives the GST-exclusive price: $1,100 - $100 = $1,000. (Check: $1,000 x 1.10 = $1,100.)