$1 - 0 = 1 ( \mathrm { cm } ) $
$3 - 0.5 = 2.5 ( \mathrm { cm } ) $
$5 - 1.5 = 3.5 ( \mathrm { cm } ) $
$8 - 3 = 5 ( \mathrm { cm } ) $
$11 - 4 = 7 ( \mathrm { cm } ) $
$14 - 5 = 9 ( \mathrm { cm } ) $
$17 - 7 = 10 ( \mathrm { cm } ) $
$1 < 2.5 < 3.5 < 5 < 7 < 9 < 10 $
实验第7天两组小麦苗的高度相差最大,相差10cm