4,5,5,6,6,7,8,9,2x,x Jika ratanya = 6,5 Maka berapakah nilai x ?

[4+(2×5)+(2×6)+7+8+9+2x+x]/10 =6,5
(4+10+12+24+3x) = 6,5 × 10
50+3x = 65
3x = 65 - 50
3x = 15
x = 15/3
x = 5

jumlah = 6,5 x banyak data = 6,5 x 10 = 65
4+5+5+6+6+7+8+9+2x + x = 65
50 + 3x = 65
3x = 65-50 = 15
x = 15/3 = 5