Since he worked for 5 hours on a $14/hour hourly waged, we have the following numerator
[tex](\$14\times5)[/tex]In those 5 hours, he mailed 300 postcards which means that he earns for each postcard mailed at
[tex]\frac{\$14\times5}{300}=0.23333...[/tex]Rounding to 2 decimal places, he earns around $0.23 per postcard.
