Gravititional acceleration on earth is approximately 9.8m/s²
The weight of the boy is directly proportional to his gravitational acceleration.
This is correct according newton's equation of bodies in motion:
Force(Also equal to weight) = Mass × Acceleration due to gravity
Here the mass is constant.
Hence decreasing the gravitational acceleration of the boy by 1/6 consequently reduces his weight by 1/6.
Therefore the boy weighs ⇒ 1/6 × 5kg × 9.8m/s² = 8.2N (rounded off to 1 decimal value)
