Abag of oranges has 144 kg. the store earns $ 3.50 per kg of orange sold. if they sold seven ninths of the sack. how much money did they earn

To find how much the store would earn if 7/9 of the 144kg of orange was sold; if each kg was sold for $3.50, you would find 7/9 of 144kg and then multiply that by the cost per kilo. 

⇒ Money earned = (7 ÷ 9) × 144 kg × (3.50 dollars/kg)
                              = $392