Question

An extra-strength aspirin contains 0.500 g of aspirin. How many grains is this? (1 grain = 64.8 mg)

Answer 1

There are 7.72 grains in .500 g of asprin 

Answer 2

The answer is 7.72 grains, this means between 7 and 8 grains.

Step-by-step explanation:

First you must have the mass in the same units, that is in g or mg. In this case the unit chosen is g. So they will convert the mass that contains a grain to g. For that you use the following Rule of Three:

If 1 mg represents 0.001 g, then how many grams are 64.8 mg?

`(64.8 mg* 0.001 g)/(1 mg) =0.0648 g`

Now, to calculate how many grains represent 0.5 g, a new Rule of Three can be used:

If 1 grain represents 0.0648 g, then how many grains are 0,5 g?

`(0.5 g*1 grain)/(0.0648 g) =7.72 grains`

So the answer is 7.72 grains.