Simple past tense and past participle of guestimate.(verb)
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Use "guestimated" in a sentence
"She said that garam masala could sub, so I took a halfway route and kind of guestimated how much of various spices to add to my garam masala (the Parsi spice blend is much bigger than a basic garam masala)."
"The Corn Growers "guestimated" a range frm 30 to 50 bushels for beans, depending on whether the beans were green enough to benefit from this week's rain, but didn't report a countywide estimate."
"It's just that with the smack trade guestimated at between"