Dyr air is about 21% oxygen.
Half of (21 over 25) = 1/2 * 21/25 = 21/50 = 0.42
21⁄25 = 0.8421 over 25 to a decimal = 0.8421/25:= 21 ÷ 25= 0.84 in decimal
21 over 25 is 84%
21/25 = 42/50
21/25 = 84/100 = 0.84 21 divided by 25 = 0.84
21/25 − 2/5 = 11/25
4/14 x 100 = 28.6% (rounded)
21/25 times 550 = 462
21/25 is already in simplest form.
25/21 is already reduced to its lowest terms
21/25 is in its simplest form.