Bible Trivia - Jacob & Esau

OK, so this trivia question comes a little late this week . . . but here it is . . .

How old was Jacob when Rebekah formulated the plan to help him "steal" his father's blessing from his brother Esau?  This is probably a story you've heard a dozen or more times so before you look it up think how old you have always pictured Jacob to be at this point. . . answer is in the next post.