Final answer:
To buy 25.5 Australian dollars, you need 2195.49 Nepalese rupees. To sell 80 Australian dollars, you get 6913.60 Nepalese rupees.
Step-by-step explanation:
To calculate how much Nepalese rupees you need to buy 25.5 Australian dollars, you can multiply the buying rate of 1 Australian dollar by 25.5. The buying rate is Rs 85.98, so Rs 85.98 multiplied by 25.5 is Rs 2195.49.
To calculate how much Nepalese rupees you get while selling 80 Australian dollars, you can multiply the selling rate of 1 Australian dollar by 80. The selling rate is Rs 86.42, so Rs 86.42 multiplied by 80 is Rs 6913.60.