Question

(520-516)*a:(3*3+8:8*21)+398=410​

Answer 1

(520-516)×a:(3×3+8:8×21)+398=410

4×a:(9+21)+398=410

4×a:30+398=410

4×a:30=410-398

4×a:30=12

4×a=12×30

4×a=360

a=360:4

a=90

Answer 2

Răspuns:

(520-516)×a:(3×3+8:8×21)+398=410

4×a:(9+21)+398=410

4×a:30=410-398

4×a:30=12

4×a=30×12

4×a=360

a=360÷4

a=90