1/100 of a pound.
since 1000/100=10, you must do 1/100 to get the weight of 10 samples.
Fraction that Sam painted in 1 min is:
10/25=2/5
Fraction that you painted in 1 min:
5/25=1/5
Fraction pained by both in 1 min:
1/5+2/5=3/5 ft²/min
Time taken to paint 50 ft² will be:
time=3/5×50=30 min
Thus we conclude that Sam was wrong.
1980mg(g/1000mg)=1.98g
2g-1.98g=0.02g or 20mg is the difference between the two weights.
