Buoyancy in air of weighed objects

A chemist uses an accurate equal-arm beam balance to weigh a sample (by placing the sample on one pan of the balance and a standard mass on the other pan of the balance). The chemist ignores the effect of upthrust and records the mass of the sample as 0.17851 kg. The density of the sample is 940.0 kg/m3, the density of the standard mass is 8493 kg/m3 and the density of air is 1.29 kg/m3. Calculate the actual mass of the sample.