Unit Rates: Jim bought a 0.3 L bottle of medicine.

Question

Jim bought a 0.3 L bottle of medicine. The dosage on the bottle is 2.5 mL per 40 kg of body weight.

 

a.) Jim weighs 176 ibs. What dosage of medicine should he take ? ( 1kg = 2.2 Ibs)

 

b.)How many doses does the bottle hold for someone of Jim's weight? ( 1 L = 1000 mL)

 

c.) Jim's wife, Susan, needs the same medicine. If Susan weighs 65 kg, how many doses are there for her in the 0.3 L bottle? 

 

d.) Explain when unit rates are useful to make comparisons. Why do unit rates make the comparisons easier? 

Answer 1

a.  176lb x 1kg/2.2lb x 2.5mL/40kg = 11mL

 

b. 0.3L x 1000mL/1L x 1 dose/11mL = 27.3 doses

 

c.  65kg x 2.5mL/40kg = 4.1mL

 

     0.3L x 1000mL/1L x 1 dose/4.1mL = 73.2 doses