The correct spelling is twentieth.
An example sentence is "for the twentieth time, spell the word correctly!"
It is spelled twentieth. (from the number name twenty, 20)
7 20ths as a percentage is 35%.
17 20ths equals 0.85
2 and 4/5ths is the same as 2 and 16/20ths. 1 and 1/4th is the same as 1 and 5/20ths. So if you add 2 and 16/20ths to 1 and 5/20ths you get 3 and 21/20ths which is the same as 4 and 1/20th.
85%
0.35
0.35
It is 0.7
0.25
40%
5 20ths in its simplest form is 1 4th, or 1 over 4, or 1/4.
0.7