Question

In a lab, a substance was cooked by 42 C over a period of 7 hours at a constant rate. What was the change in temperature each hour

Answer 1

Given that we have the change in temperature over 7 hours and we are looking for the change over 1 hour, we can divide the total change in temperature by 7. Thus, the change in temperature would be $\frac{42}{7} C^{\circ}$.

Additionally, this can be solved by equations:

$\dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = \dfrac{x \,\textrm{C}^{\circ}}{1 \,\textrm{hour}}$

$1 \,\textrm{hour} \cdot \dfrac{42 \,\textrm{C}^{\circ}}{7 \,\textrm{hours}} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} \,\textrm{C}^{\circ} = x \,\textrm{C}^{\circ}$

$\dfrac{42}{7} = x$

By using two different methods, we can determine that the change each hour was equal to 42/7 C° per hour.