Celebrate in style with this unique black t-shirt! Featuring a playful design with a square root of 121 (which equals 11), creatively presented amidst a background of colorful math equations. "Years Old" is printed below to complete the fun birthday theme. This eye-catching shirt is perfect for math lovers or anyone celebrating their 11th birthday with a touch of humor. Made from comfortable materials, it's ideal for casual wear, birthday parties, or as a fun gift. Grab this conversation-starter tee and showcase your unique style!