Jawapan

2015-10-07T20:26:16+08:00
X ialah 9 . guna formula minĀ 
2015-10-07T22:27:32+08:00
(6 +10 +13 + x +7) /5 = x

(36 + x) /5 = x

36 + x = 5x

5x - x = 36

4x = 36

x = 36 /4

x = 9