Nandini house is 9/10 km from her school. She walked some distance and then took a bus for ½ km to reach the school. How far did she walk?

Total distance between school and house = 9/10km
Distance covered by bus = 1/2 km
Remaining distance= 9/10-1/2=9×1-1×5/10 [L.C.M. of 10 and 2 is 10]
= 9-5/10=2/5 km.
Therefore, the distance covered by walking us 2/5 km

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