Learn a Fact: 3 x 7 This picture and story will help you remember 3 x 7 = 213 (Tree) x 7 (Surfin) = 21 (Denty Sun)To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 videoFact Navigator You're learning7x3213x721 Move on to other facts: Back Next 7 X 2 14 7 X 4 28 View All Facts