Question

A health department estimates that it needs 4 vials of malaria serum to treat 50 people. How many vials are required to treat 875 people?

Answer 1

70 vials

Explanation:

Assuming the proportion holds, ...

... vials/people = x/875 = 4/50

Multiplying by 875, we get

... x = 875·4/50 = 70

70 vials are neede to treat 875 people.

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If the vials only come in packages of 4, then 72 vials (18 packages) are needed