STEVE INSKEEP, HOST:

Good morning. I'm Steve Inskeep. Sanaa Hiremath has a knack for numbers. The 11-year-old Florida student solves math in her head. She's autistic and struggled with taking written tests, but once she was home-schooled, she found she could do it without the writing. Now she has a Guinness World Record, finishing a 12-digit multiplication problem in under 10 minutes - no calculator, no paper, nothing. Twelve digits in 10 minutes - how many digits is that per minutes? Never mind. It's MORNING EDITION. Transcript provided by NPR, Copyright NPR.