math for nursing[Order: Erythromycin 750 mg On hand: Erythromycin 250 mg capsules Desired (D) = 750 mg On hand (H) = 250 mg Vehicle (V) = 1 capsule]

Desired (D) = 750 mg
On hand (H) = 250 mg
Vehicle (V) = 1 capsule

Computation:
250 (H) : 1 (V) = 750 (D) : x

Multiply the extremes and the means:

250x = 750
x=3 capsules

Answer: 3 capsules