oxygen
Helium is lighter (less dense) than oxygen & nitrogen.
Nitrogen is four fifths of the air so their densities are very similar. Pure nitrogen is slightly less dense than air.
"One less than four times a number" refers to an expression in algebra. If we let the number be represented by a variable, say ( x ), then "four times a number" is ( 4x ). Therefore, "one less than four times a number" can be written as ( 4x - 1 ). This expression indicates that you take four times the value of ( x ) and then subtract one from it.
6a-4
10x - 4
4n - 1
4n-5 (Which is four times a number minus 5)
4n-6
1
There are two possible answers:9 * 2 - 4 = 14, or four less than the quantity nine times two(9 - 4) * 2 = 10, or two times the quantity nine minus four
4x - 5
14-4x6=