Find the discount amount, then subtract from the usual price.<br><br>
&bull; Usual price: \(\$8\)<br>
&bull; Discount: 25% of \(\$8 = \frac{25}{100} \times 8 = \frac{1}{4} \times 8 = \$2\)<br>
&bull; Sale price: \(\$8 - \$2 = \$6\)<br><br>
Alternatively: 75% of \(\$8 = \frac{75}{100} \times 8 = \frac{3}{4} \times 8 = \$6\).<br><br>
Jerry has to pay \(\$6\) for the book.<br>
Check: \(\$6 \div \$8 = 0.75 = 75\%\), which is 100% - 25% = 75%. ✓<br><br>
Final Answer: \(\$6\)