30/50 of earth atomospere is made up nitrogen while only 21/100 is made up of oxygen what fraction of earth atmosphere is either nitrogen or oxygen

81/100 of the atmosphere consists of those two elements

Step-by-step explanation:

3/5+21/100  >  81/100

answer: options

step-by-step explanation:

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.