a÷6× 6÷7×7=8+8-9÷9 cum se face acest exercitiu?

Răspuns :

a÷6× 6÷7×7=8+8-9÷9

a : 6 × 6 : 7 × 7 = 16 - 1

a : 6 × 6 : 7 × 7 = 15 |×42

a × 42 = 15 × 42 | : 42

a = 15
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