Tolong di jawab dengan jalan yaa

jika perbandingan berikut senilai tentukanlah nilai yang belum diketahui
A : a:5 = 16 : 20
B : 40 : ( X + 3 ) = 5 : 2

Tolong di jawab dengan jalan yaa

A. a : 5 = 16 : 20

20 x a = 16 x 5

20a = 80

a = 80 : 20

a = 4

B. 40 : (X + 3) = 5 : 2

5(X + 3) = 40 x 2

5X + 15 = 80

5X = 80 – 15

5X = 65

X = 65 : 5

X = 13

A.
$frac{a}{5} = frac{16}{20} \ 20 times a = 16 times 5 \ 20a = 80 \ a = 80 div 20 \ a = 4$
B.
$frac{40}{x + 3} = frac{5}{2} \ 40 times 2 = 5 times < x + 3 > \ 80 = 5x + 15 \ 80 - 15 = 5x \ 5x = 65 \ x = 65 div 5 \ x = 13$