Using mathematic equations, would these be correct?

nerte ar nelde na yunque 9 + 3 = 12
nerte [1]píca nelde na enque 9 - 3 = 6
nerte nellume na otso yuquaine 9 × 3 = 27
nerte [2]neldesta na nelde 9 ÷ 3 = 3


[1] píca adj. less; from píca- v. to lessen.
[2] neldesta v. distributed in three even portions; from nelde + estat-