Question

tolong jawaban beserta cara kerjanya​

Answer 1

Jawaban:

C. 90

Penjelasan:

Misalkan nilai mata pelajaran kelima = a

Rata rata:

[tex] = \sf \dfrac{jumlah\: nilai}{banyak \: nilai} [/tex]

[tex] = \dfrac{82 + 94 + 86 + 78 + a}{4 + 1} = 86[/tex]

[tex] = \dfrac{340 + a}{5} = 86[/tex]

[tex] = 340 + a = 5(86)[/tex]

[tex]340 + a = 430[/tex]

[tex]a = 430 - 340[/tex]

a = 90

Jawabannya C.