Math Problem:
(PLEASE HELP ME I WILL GIVE BRAINLIEST)

Tammy figured her math exam would be difficult unless she put in at

least 15 hours of study time to prepare. She studied 2½ hours on

Monday, 3 hours on Tuesday, 4¾ hours on Wednesday, and 4 ½

hours on Thursday. Did she study at least 15 hours? Explain.