Chapter 21 - Electric Current and Direct-Current Circuits - Problems and Conceptual Exercises - Page 754: 3

$9.375\times 10^{19}\frac{electrons}{s}$

As we know that $\frac{N}{\Delta t}=\frac{I}{e}$ We plug in the known values to obtain: $\frac{N}{\Delta t}=\frac{15}{1.6\times 10^{-19}}$ $\frac{N}{\Delta t}=\frac{15}{1.6\times 10^{-19}}$ $\frac{N}{\Delta t}=9.375\times 10^{19}\frac{electrons}{s}$