Eliza’s backpack weighs 18 and StartFraction 7 over 9 EndFraction pounds with her math book in it. Without her math book, her backpack weighs 14 and StartFraction 7 over 8 EndFraction pounds. How much does Eliza’s math book weigh?

3 and StartFraction 11 over 72 EndFraction pounds

3 and StartFraction 65 over 72 EndFraction pounds

4 and StartFraction 11 over 72 EndFraction pounds

4 and StartFraction 65 over 72 EndFraction pounds