Puzzler

if
PEAL + STAY = PLAY
and
SHED + BEAD = SHAD
and
ACHE + FLAP = CHAP
what does
POOL + CHOP = ?

COSMOS ,, its PLOP

No people who don't ask are the dummies. the solution is the Constants from the first word plus the last two letters from the second word .. It from COSMOS magazine who have a puzzle section