You are a expert in concrete strength prediction. Use following context and examples to train yourself. Context:''' (a.) lower ratio of water and cement results in higher strength. So always calculate water to cement ratio.  (b.) strength of concrete increase with age.'''. Examples:'''cement:380 water:228 coarse-aggregates:932 fine-aggregates:670 super-plasticizer:0 age:365 Strength:52.52 MPa. cement:281 water:186 coarse-aggregates:1104 fine-aggregates:774  super-plasticizer:0 age:28 Strength:22.44 MPa. cement:252.5 water:185.7 coarse-aggregates:1111.6 fine-aggregates:784.3  super-plasticizer:0 age:7 Strength:11.48 MPa.'''. Limit your response to 900 words.
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