now, a decigram is "deci" one tenth of a gram, 1/10 gram.
whilst a milligram is "milli" one thousandth of a gram, 1/1000 gram
now, the flea is 8 of those decigrams thus is 8 * (1/10) grams
the ant is 3 of those milligrams thus 3 * (1/1000) grams
let's find their difference.
