It is 83 because it is a Prime number
83
The composite numbers are: 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86 ,87, 88
The only prime numbers between 81 and 90 is... 83
72.......107-98(9) 98-90(8) 90-83(7) 83-77(6) 77-[72](5) 72-68(4) 65
96 +90 81=267 Whats <267/3? ^267 divided by 3 is =83
The MAD is 8.
81, 82, 84, 85, 86, 87, 88. 80 and 90 are composite too
The odd numbers between 70 and 90 are 71, 73, 75, 77, 79, 81, 83, 85, 87, and 89. We know right away that 75 and 85 are composite, since they're divisible by 5. 81 is composite since it is the square of 9. 77 is obviously divisible by 11, so it, too, is composite. 87 is divisible by 3 since 8 + 7 = 15, which is divisible by 3. Therefore, and trust me, I double-checked the rest, 75, 77, 81, 85, and 87 are the composite, odd numbers between 70 and 90.
83
160
60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90 are the composite numbers in that range.
For 77 83 69 72 85 90 95 75 55 45: σ=15.4071