The U was lost long ago in the English form, as was the O in twenty and the E's in thirty. Only sixty, seventy, eighty, and ninety retain the unit name in their tens values.
No it's spelled forty.
You have spelled it out correctly.
The number 45 in English is spelled forty-five. It is never spelled fourty-five.
The number 46 is spelled "forty six", normally hyphenated as "forty-six".
348 is spelled as three hundred forty-eight.
Sometimes 40 is spelled as forty because it sounds proper. Depending on what you are trying to say, either or could look better with the sentence.
47 is spelled out, 'forty-seven'.
"Forty thousand" in numbers is "40,000"
Forty-one Forty-two Forty-three Forty-four Forty-five Note: 4 = Four 14 = Fourteen 40 = Forty as in letter u is omitted in 40
The form "forty," like twenty, thirty, and fifty lost its original form due to changes in English pronunciation. It may be spelled that way because in some dialects, four is "fo-er" hence the need for a "U." But when saying forty, there is no other vowel so it simply excluded from the word due to simplicity.
because that is how it sounds
It is spelled forty-four.