So far, time spent practicing backstroke, breaststroke, and butterfly is 50 + 9 + 121 = <<50+9+121=180>>180 hours
Since Rita’s must swim 1500 hours, the freestyle and sidestroke practice sessions will take 1500 - 180 = <<1500-180=1320>>1320 hours
Rita will practice for 220 hours/month, meaning she will meet her coach’s target in 1320/220 = 6 months.
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