A duck’s mass at birth was 0.05 kilogram. The duck gained approximately 0.042 kilograms each week.
After how many weeks is the duck’s mass 0.890 kilograms?
The duck gained 0.042 kilograms per week, so we can express its mass as a linear function of weeks as M = 0.042W + 0.05, where M is the mass in kilograms and W is the number of weeks.
We want to find the number of weeks when the mass is 0.890 kilograms, so we can set up the equation:
0.890 = 0.042W + 0.05
Subtracting 0.05 from both sides:
0.89 - 0.05 = 0.042W
0.84 = 0.042W
Dividing both sides by 0.042:
W = 0.84 / 0.042
W ≈ 20
Therefore, the duck's mass will be 0.890 kilograms after approximately 20 weeks.