`""_(75)Re^(162)rarr""_(z_1)X^(A_1)+` एल्फा कण
`""_(74)Re^(188)rarr""_(z_2)Y^(A_2)+` बीटा कण A2-A1/Z2-Z1= ?

Answer

15

Explanation

`""_(75)Re^(162)rarr""_(73)Ta^(158)+""_2He^4`
`""_(74)Re^(188)rarr""_(75)Re^(188)+""_(-1)e^0`
`{:(188-158),(bar("75 - 73 ")):}=30/2=15`