The wound, initially with an area of 90 cm2
, heals according to the formula
A(t) = 90(10
−0.023t), where A(t) is the area of the wound in square centimeters after t,
days of healing.
a) How big will the wound be once it is 70% healed? [1K]
b) In how many days will 70% of the wound be healed? [3T]
If you mean A(t) = 90*10^(-0.023t) then
(a) 0.30 * 90
(b) 10^(-0.023t) = 0.30