Mass fraction of fat in butter is 82.5%. Milk of what mass, fat content (i.e. mass fraction of fat)

Mass fraction of fat in butter is 82.5%. Milk of what mass, fat content (i.e. mass fraction of fat) is 3.2%, is it necessary to obtain butter weighing 100 kg?

Given:
ω (fat in oil) = 82.5%
ω (fat in milk) = 3.2%
m (oil) = 100 kg

Find:
m (milk) -?

1) m (fat in oil) = ω (fat in oil) * m (oil) / 100% = 82.5% * 100/100% = 82.5 kg;
2) m (fat in milk) = m (fat in oil) = 82.5 kg;
3) m (milk) = m (fat in milk) * 100% / ω (fat in milk) = 82.5 * 100% / 3.2% = 2578.125 kg.

Answer: The mass of milk is 2578.125 kg.