Question
PSLE
Penelope had a bottle of dettol. She used an equal amount of dettol each day. At the end of the 12th day, 13 of the bottle was left. At the end of the 16th day, the amount of dettol left was 400 mℓ. What was the amount of dettol in the bottle at first? Express your answer in mℓ.
2 m

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PSLE
Penelope had a bottle of dettol. She used an equal amount of dettol each day. At the end of the 12th day, 13 of the bottle was left. At the end of the 16th day, the amount of dettol left was 400 mℓ. What was the amount of dettol in the bottle at first? Express your answer in mℓ.