Total vadapavs made = 500
Vadapavs with chicken and mushroom patty =250 (Number of terms in the series 1,3, 5, 7, 9...499) out of which half of the vadapavs also have vegetable petty.
Vadapavs with only mushroom patty = 36 (Number of terms of the series 8, 22, 36, ….)
Vadapavs with chicken, mushroom and vegetable patty = 18 (Number of terms in the series 1, 29, 57...
Required answer = 500 − 250 – 36 = 214.