21st Birthday T-Shirt | Square Root of 441 – 21 Years Old-T-Shirt

Solid colors: 100% Cotton; Heather Grey: 90% Cotton, 10% Polyester; All Other Heathers: 65% Cotton, 35% Polyester, Imported, Machine wash cold with like colors, dry low heat, Fun and; comfy 21 yrs old math T-shirt featuring a simple mathematics problem on a math shirt to make your son, daughter, children, child smile on their twenty first birthday, 21st bday. A great geeky nerdy math tee shirt 21 year old birthday gift idea for a proud math geek, math nerd, science fan, science geek or science nerd. Great basic math clothing for boys and girls, unisex. For a loose fit, please order a size up. Lightweight, Classic fit, Double-needle sleeve and bottom hem