Carlo is a first-year student. At midterm, he goes to meet with his business statistics professor during office hours. Carlo desperately wants to major in business, and this course is a requirement to do so. Unfortunately, after his abysmal performance on the first two quizzes and his midterm exam, he's failing the class. Carlo studied for weeks, attended extra study sessions with the TA, and joined a study group. He doesn't understand why he isn't doing better on his quizzes and exams. Carlo tells his instructor that he has always struggled to recognize numbers and symbols, memorize facts, and understand abstract concepts such as place values and fractions. Carlo's professor suggests Carlo visits the campus learning center to be screened for a possible learning disability. What learning disability does it sound like Carlo may have?