Question

Christina's time for a race was 34.6 seconds. Another runner's time was 6.85 seconds faster. Write and evaluate an equation with a variable to find the difference between Christina's time and the other runner's time.

a) (34.6 - a = 6.85)
b) (34.6 + a = 6.85)
c) (34.6 × a = 6.85)
d) (34.6 ÷ a = 6.85)

Answer 1

The correct equation to find the difference between Christina's time and the other runner's time is (34.6 - a = 6.85), where 'a' is the time of the other runner. By solving this equation, we find that the other runner's time was 27.75 seconds.

Step-by-step explanation:

The question asks us to find the difference in race times between Christina and another runner. To find this, we need to set up an equation where the variable represents the time of the other runner. The correct equation is:

(34.6 - a = 6.85)

Where 'a' represents the time of the other runner. Since the other runner's time was 6.85 seconds faster, we subtract 'a' from Christina's time to find the faster time. By solving the equation:

34.6 - a = 6.85
→ a = 34.6 - 6.85
→ a = 27.75

Therefore, the other runner's time was 27.75 seconds, which makes it 6.85 seconds faster than Christina's 34.6 seconds.