Dane liczby: a, b, c, d i a > b, a > c i a > d
[tex]\frac{a + b + c + d}{4} = 27 \ \ \ |\cdot 4 \\ a + b + c + d = 108 \\ b + c + d = 108 - a \\\\ \frac{\frac{a}{2} + b + c + d}{4} = 27- 6 \\ \frac{\frac{a}{2} + b + c + d}{4} = 21 \ \ \ |\cdot 4 \\ \frac{a}{2} + b + c + d = 84 \\ \frac{a}{2} + 108 - a = 84 \\ \frac{a}{2} - a = 84 - 108 \\ -\frac{a}{2}= -24 \ \ \ |\cdot (-2) \\ a = 48[/tex]
Odp. A
