Denise’s birthday brainteaser - Did you solve it? | Alex Bellos’ puzzles

Alex Bellos set you a challenge: the sequel to Cheryl’s birthday puzzle. Did you manage to solve it? Subscribe to Guardian Science and Tech ► Watch Alex work it out and see if your answer matches. See you in two weeks for the next puzzle! The Guardian on YouTube: The Guardian ► Watch Me Date ► Guardian Football ► Guardian Music ► Guardian Australia ► Guardian Culture ► Guardian Wires ► Guardian Food ►