61
a third of 21 is 7
40/21
1/7 x 21 = 21/7 = 3
A polygon with 21 sides is called an Icosagon.
The prime factors of 21 are 3 and 7. 3 x 7 = 21
XLII in Roman numerals [50-10 + 2]
21/40 = 0.525
There are 21 037 950.6 minutes in 40 years.......
Yes, 40 is forty.
There have been 23 popes named John but none with 21 as a maximum.
A fourth of twentyone = 21/4 = 5.25 and that, as a percentage, is 525%
21/100 ( Twentyone hundredths).