The oil sands near Fort McMurray, AB are a major contributor to Canada¡¯s oil production. The oil sands are 15 % oil, the remainder being solid sand particles. In the initial stages of processing, the oil sands are mixed with warm water and sent to a settling tank. In the settling tank three layers are formed: a bottom layer containing 95 % sand and 5 % water, a middle layer of 5 % oil and 95 % water, and a top layer of 70 % oil and 30 % water. The top layer is skimmed off and sent for further processing while the bottom two layers are sent for disposal. How much warm water is added to 100 tonnes of oil sands in this process if 90 % of the total oil is recovered in the top layer? All percentages given are weight percentages.
Àú¿¡°Ô´Â ¹°Áú ¼öÁö°¡ ¾î·Æ³×¿ä. µµ¿ÍÁÖ¼¼¿ä.