Answer:
5 capsules
Explanation:
A doctor may prescribe Keflex for an ear infection. One capsule = 0.250 g of Keflex. The recommended daily dose for a child is (40.0mg of Keflex)/(kg that the child weighs).
Step 1
We convert the capsules form grams to milligrams
1 gram = 1000 milligrams
0.250grams = x
Cross Multiply
x = 0.250 × 1000 milligrams
x = 250 mg
Hence, 1 capsule = 250 mg
How many Keflex capsules would a 69-pound child take for one daily dose? (Round to the nearest whole number of capsules) Given: 1 pound = 0.453592 kg
The recommended daily dose for a child is (40.0mg of Keflex)/(kg that the child weighs).
The child weighs 69 pounds
1 pound = 0.453592 kg
69 pounds = x kg
Cross Multiply
x kg = 69 × 0.453592kg
x kg = 31.297848kg
Hence,
1 kg= 40.0 mg
31.297848 kg = x
x = 31.297848 × 40.0mg
x = 1251.91392mg
Therefore, the child would take 1251.91392 mg
From the first calculation we know that:
1 capsule = 250 mg
250mg = 1 capsule
1251.91392 mg = x capsules
250mg × x = 1251.91392 mg × 1 capsule
x = 1251.91392 mg/250mg
x = 5.00765568 capsules
Approximately = 5 capsules
Hence, a child that weighs 69 pounds takes 5 capsules of keflex