Muffy weighs 12 - 3 = <<12-3=9>>9 ounces

Puffy weighs 5 + 9 = <<5+9=14>>14 ounces.

If Brittany weighs both Puffy and Muffy, the scale would read 9 + 14 = <<9+14=23>>23 ounces

# Answer

23
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Brittany has 3 gerbils: Puffy, Muffy, and Scruffy. Puffy weighs 5 ounces more than Muffy. Muffy weighs 3 ounces less than Scruffy.  If Scruffy weighs 12 ounces, how much would the scale indicate, in ounces, if Brittany put Puffy and Muffy on the scale?
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23
Brittany has 3 gerbils: Puffy, Muffy, and Scruffy. Puffy weighs 5 ounces more than Muffy. Muffy weighs 3 ounces less than Scruffy.  If Scruffy weighs 12 ounces, how much would the scale indicate, in ounces, if Brittany put Puffy and Muffy on the scale?
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