Answer
(a) $20m/s$
(b) $20.25\frac{m}{s}$
Work Step by Step
(a) We can calculate $v_{avg}$ as follows:
$v_{avg}=\frac{1}{11}\Sigma ^{25}_{k=15}k$
By plugging and summing up the known values, we obtian:
$v_{avg}=\frac{220}{11}$
$\implies v_{avg}=20\frac{m}{s}$
(b) We can determine $v_{rms}$ as follows:
$v_{rms}=\sqrt{v_{avg}^2}$
We plug in the known values to obtain:
$v_{rms}=\sqrt{\frac{1}{11}\Sigma ^{25}_{k=15}k^2}$
We plug in the known values to obtain:
$v_{rms}=\sqrt{\frac{1}{11}\times 4510}$
$\implies v_{rms}=20.25\frac{m}{s}$
