LIC AAO Model Paper 4

7x+ 6y - 4z = 122 ... (I)
4x- 5y - 3z = 88 ... (II)
9x- 2y - z = 78 ... (Ill)
By equation (III) x 3 - equation (II),
27x - 6y - 3z = 234
4x - 5y - 3z = 88
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23x + y = 146 (IV)
By equation (III) x 4 equation (1),
36x+ 8y + 4z = 312
7x - 6y -4z = 122
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29x+2 y =190 ... (v)
By equation (lV) x 2 - equation (v),
46x + 2y = 292
29x+2 y = 190
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17x = 102 ...(lV)
⇒ x = 6 From equation (lV),
23 x 6 - y = 146
⇒ y = 146 - 138 = 8
From equation (III),
9x6-2x8-2 = 78
⇒ 54 + 16 + z = 78
⇒ z = 78 - 70 = 8
Clearly, x < y = z