Answer:
<em>X ∈ { 96, 102, 108, 114, 120, 126, 132, 138, 144, 150, 156, 162, 168, 174, 180, 186, 192, 198, 204, 210, 216, 222, 228, 234, 240, 246, 252, 258, 264, 270, 276, 282, 288, 294, 300, 206, 312, 318, 324, 330, 336, 342, 348, 354, 360, 366, 372, 378, 384, 390, 396, 402, 408, 414 }</em>
Step-by-step explanation:
See procedure below;
Set X { all multiples of 6 between 15 and 70, provided multiples belong to the set of natural numbers },
Set X { 6n | 15 < n < 70, n ∈ natural numbers },
n ∈ { 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.........69 },
X ∈ { 96, 102, 108, 114, 120, 126, 132, 138, 144, 150, 156.........414 }
<em>Answer; { 96, 102, 108, 114, 120, 126, 132, 138, 144, 150, 156, 162, 168, 174, 180, 186, 192, 198, 204, 210, 216, 222, 228, 234, 240, 246, 252, 258, 264, 270, 276, 282, 288, 294, 300, 206, 312, 318, 324, 330, 336, 342, 348, 354, 360, 366, 372, 378, 384, 390, 396, 402, 408, 414 }</em>