ANSWERS: Ava’s Acorns: Ava brought home 49 acorns, 5 + 10 + 15 + 19 = 49 total; Alien Message: The secret message is “We came here to party!”; Triangulate It! The center number is the product of the three corner numbers, so the missing number is 24; Makayla’s Mask: Makayla bought the Mummy mask for $2.15 using two $1 bills, a dime, and a nickel. Another possible answer: Makayla bought the $3.60 mask wih a $1 bill, a $2 bill, a half-dollar coin, and a dime.