9. higher order thinking the price of stock a at 9 a.m. was $15.75. since then, the price has been…

9. higher order thinking the price of stock a at 9 a.m. was $15.75. since then, the price has been increasing at the rate of $0.05 per hour. at noon, the price of stock b was $16.53. it begins to decrease at the rate of $0.13 per hour. if the stocks continue to increase and decrease at the same rates, in how many hours will the prices of the stocks be the same?
Answer
Explanation:
Step1: Calculate Stock A's price at noon
From 9 A.M. to noon is 3 hours. Stock A's price at noon is $15.75+0.05\times3=15.75 + 0.15=15.9$.
Step2: Set up an equation for when the stock prices are equal
Let $t$ be the number of hours after noon when the prices are the same. The price of Stock A after $t$ hours is $15.9 + 0.05t$, and the price of Stock B after $t$ hours is $16.53-0.13t$. Set them equal: $15.9 + 0.05t=16.53-0.13t$.
Step3: Solve the equation for $t$
Add $0.13t$ to both sides: $15.9+0.05t + 0.13t=16.53-0.13t+0.13t$, which simplifies to $15.9 + 0.18t=16.53$. Then subtract 15.9 from both sides: $0.18t=16.53 - 15.9=0.63$. Divide both sides by 0.18: $t=\frac{0.63}{0.18}=3.5$.
Answer:
3.5