of the students in the school band, 11/13 play a brass instrument, 3/9 play the tuba. What fraction of the students in the band play the tuba?

Adoctor administers a drug to a 38-kg patient, using a dosage formula of 50 mg/kg/day. assume that the drug is available in a 100 mg per 5 ml suspension or in 500 mg tablets. a. how many tablets should a 38-kg patient take every four hours? b. the suspension with a drop factor of 10 ggt/ml delivers the drug intravenously to the patient over a twelve-hour period. what flow rate should be used in units of ggt/hr? a. the patient should take nothing pills every four hours. (type an integer or decimal rounded to the nearest hundredth as needed.)

Ten times the square of a non-zero number is eqaul to ninety times the number

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?