Question 20
A racing turtle travels along a straight line as follows. On the first stretch, of length $\frac12\,\mathrm m$, it runs at $3\,\mathrm{m/s}$. On the second stretch, of length $\frac13\,\mathrm m$, it runs at $4\,\mathrm{m/s}$. On the third stretch, of length $\frac14\,\mathrm m$, it runs at $5\,\mathrm{m/s}$, and so on.
a) How long does it take to cover the first stretch? Write the result as the difference of two unit fractions, that is, fractions with numerator 1.
b) Do the same for the second stretch.
c) Calculate the time needed to cover the first 2013 stretches.
a) How long does it take to cover the first stretch? Write the result as the difference of two unit fractions, that is, fractions with numerator 1.
b) Do the same for the second stretch.
c) Calculate the time needed to cover the first 2013 stretches.