i'm newbie in haskell, and i have question: i write code:

word_list = ["list", "lol", "wordword"]
check str = if head str == 'l' then tail str else str
average wl = (length $ concat $ map check wl) `div` length wl

this code must delete first "l" symbol in every word in word list, concat recieved words, get length of result string and div on words count.

so in this code i must recieve: 13 / 3 = 4,333... ("listlolwordword" = 15, "istolwordword" = 13) but i recieve just 4.

average :: [[Char]] -> Float don't work, i recieve error. where my mistake? ps. sorry my english, please

haskell
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