Answer: she sold 1.62 kilograms of apple at the farmer's market.
Step-by-step explanation:
The total number of pears and apples that the farmer sold at the farmer's market is 8.1 kilograms.
If 4/5 of this weight is pears and the rest is apples. it means that the total weight of pears that the farmer sold
at the farmer's market is
4/5 × 8.1 = 0.8 × 8.1 = 6.48 kilograms.
Therefore, the number of kilograms of apples that she sold at the farmer's market is
8.1 - 6.48 = 1.62 kilograms
