(a) which curve fits the data best? figure 1 figure 2 figure 3 (b) use the equation of the best - fitting…

(a) which curve fits the data best? figure 1 figure 2 figure 3 (b) use the equation of the best - fitting curve from part (a) to predict the amount of the radioactive substance after 30 days. round your answer to the nearest hundredth. milligrams

(a) which curve fits the data best? figure 1 figure 2 figure 3 (b) use the equation of the best - fitting curve from part (a) to predict the amount of the radioactive substance after 30 days. round your answer to the nearest hundredth. milligrams

Answer

Explanation:

Step1: Visual inspection

Visually, Figure 1 and Figure 2 have exponential - decay functions ($y = 531(0.98)^x$ and $y=200(0.93)^x + 50$), which are typically for decay processes. Figure 3 has a quadratic function ($y = 0.03x^2-8x + 575$). Since the data points seem to follow a decay - like pattern more closely and the points in Figure 1 seem to be closer to the curve compared to Figure 2, Figure 1 fits the data best.

Step2: Prediction using the best - fitting equation

The best - fitting equation is $y = 531(0.98)^x$. Substitute $x = 30$ into the equation. $y=531\times(0.98)^{30}$ First, calculate $(0.98)^{30}$. Using the formula $a^n=e^{n\ln(a)}$, we have $\ln(0.98)\approx - 0.0202$ and $n = 30$, so $n\ln(a)=30\times(-0.0202)=-0.606$. Then $(0.98)^{30}=e^{- 0.606}\approx0.545$. Now, $y = 531\times0.545=289.395\approx289.40$

Answer:

(a) Figure 1 (b) $289.40$