When the equation n=o/p is solved for p correctly, the equation should read:

Given the equation N=O/P, solve for P by multiplying the left and right by P/N:

N * P/N = O/P * P/N

P = O/N

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer