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Adding probabilities

Harry Potter is at Ollivanders Wand Shop. As we all know, the wand must choose the wizard, so Harry cannot make the choice himself. He interprets the wand selection as a random process so he can determine the probabilities of different outcomes.
The wood types available are holly, elm, maple, and wenge. The core materials on offer are phoenix feather, unicorn hair, dragon scale, raven feather, and thestral tail.
Let AA be the event that Harry is chosen by a wand made of holly and BB be the event that he is chosen by a wand with a dragon scale core.
What is P(A or B)P(A\text{ or }B), the probability that Harry is chosen by a wand made of holly or a wand with a dragon scale core?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
Phoenix featherUnicorn hairDragon scaleRaven featherThestral tail
HollyHolly PhoenixHolly UnicornHolly DragonHolly RavenHolly Thestral
ElmElm PhoenixElm UnicornElm DragonElm RavenElm Thestral
MapleMaple PhoenixMaple UnicornMaple DragonMaple RavenMaple Thestral
WengeWenge PhoenixWenge UnicornWenge DragonWenge RavenWenge Thestral