Answer:
[tex]13.51\ \text{s}[/tex]
Step-by-step explanation:
[tex]s[/tex] = Average speed of Sandra = [tex]7.4\ \text{m/s}[/tex]
[tex]d[/tex] = Distance Sandra ran = [tex]100\ \text{m}[/tex]
Time is given by
[tex]t=\dfrac{d}{s}[/tex]
[tex]\Rightarrow t=\dfrac{100}{7.4}[/tex]
[tex]\Rightarrow t=13.51\ \text{s}[/tex]
The time it takes Sandra to run the given distance is [tex]13.51\ \text{s}[/tex].
