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
The MAD is 8.
96 +90 81=267 Whats <267/3? ^267 divided by 3 is =83
83 and 89
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.