(a+b+c)² =49

Again, (a+b+c)² = a² + b² + c² + 2(ab + bc + ac)

Thus, 35 + 2(ab + bc + ac) = 49

Or, (ab + bc + ac) = 7

Again, we know, a³ + b³ + c³ - 3abc = (a+b+c){(a² + b² + c²) - (ab + bc + ac)}

Or, 151 - 3abc = 7(35 - 7)

Or, -3abc = 7×28

Or, abc = 196/(-3)

Or, abc = -15

Hence, Answer is (-15)