Having trouble with your homework assignments? Not sure how to convert the quantities indicated in an American recipe into the metric system? Regardless of why you need to convert ounces to grams, you don't have to worry doing it is really simple. The only operation to be performed is the multiply the number of ounces by the coefficient 28, 35.
Steps
Method 1 of 3: Perform a Quick Conversion
Step 1. Make a note of the number of ounces and assign the unit of measurement "ounces" or "oz"
Take an example problem as a guide. Suppose you need to convert the quantities of ingredients in a recipe expressed in ounces to grams. If the recipe says you should use eight ounces of chicken, you will need to make a note of the following text: 8 oz or 8 oz.
Step 2. Multiply this value by the coefficient "28, 35"
This is the conversion coefficient that allows you to convert a value expressed in ounces into grams. The number you get from the calculation will be the equivalent expressed in grams.
- In the example problem you will have to multiply 8 ounces by 28, 35 to get the result 226.8 grams of chicken.
- Do not forget to report together with the numerical result also the unit of measurement which will be grams or "g". This is especially true in the school environment, as it may give you a lower than expected rating.
Step 3. If you need to perform very precise calculations, multiply the value to be converted by the coefficient 28, 349523125
The value 28.35 used in the previous step does not indicate the correct number of grams corresponding to an ounce. The coefficient indicated in this step is much closer to the real value, since it includes a large number of decimals. For this reason, if the scope in which you need to convert requires very accurate precision, use the latter. In other case you can safely use the initial coefficient that is 28, 35.
In the example problem, wanting to obtain a high precision regarding the quantity of chicken to use, you will have to multiply the number 8 by 28, 349523125 obtaining as a result 226, 796185 grams. However, as you can see, the difference is very small.
Method 2 of 3: Convert Without Calculator
Step 1. Do the multiplication using the coefficient 30
If you are unable to use a calculator, try using the conversion coefficient shown to simplify manual calculations. Multiply the value to be converted by 30. The calculation to perform is very simple, since it is equivalent to multiplying the value to be converted by 3 and then adding a final 0.
Try using this system to convert 8 ounces to grams. Proceed by multiplying 8 by 30 which is the same as multiplying 8 by 3, which results in 24, and add a final 0 to get 240.
Step 2. Calculate 10% of the final result you got
Also in this case the calculation is very simple since it is enough to eliminate the final 0. In other words, this is the value you got by multiplying the number to convert by 3.
In the initial example, 10% of 240 equals 24
Step 3. Now subtract the value obtained in the previous step from the conversion result
Using this method you will be able to correct the error due to the use of a conversion coefficient different from the real one (30 instead of 28, 35), but it will still allow you to get a result very close to the correct one and without using the calculator.
Half of 24 is 12, so you get 240 - 12 = 228 grams. As you can see the result you got is very close to the correct one, that is 226.8 g, and you didn't have to use the calculator.
Method 3 of 3: Use a Conversion Factor
Step 1. Make a note of the value to be converted and express it as a fraction
This method uses fractions to show how the units, ounces and grams, relate to each other. Start by writing the number of ounces to convert to the numerator of the fraction, i.e. the top. At this point, return the number "1" to the denominator of the same fraction, ie the underlying part. In the latter case, do not report any unit of measurement.
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Suppose you are struggling with a chemistry experiment that will generate 1.23 ounces of product at the end of the reaction. In order to convert the amount of product obtained into grams, you will need to start with the following fraction:
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- 1.23 ounces / 1
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- Also in this case do not forget to report the units of measure to the numerator of the fraction. This step is critical to achieving a successful conversion using this method.
Step 2. Multiply the resulting fraction by the following fractional number 1 gram / 0.035 oz
This is the conversion factor that allows you to convert ounces into grams and vice versa. Basically it is a fraction that shows the relationship between ounces and grams. For the moment, doing the multiplication focuses attention only on the numbers, leaving out the units of measurement. If you have trouble multiplying fractions, refer to this guide.
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In the example problem you will need to perform the following calculations:
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- 1, 23 × 1 = 1, 23
- 1 × 0, 035 = 0, 035
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- So the final fraction you will get is 1, 23/0, 035.
Step 3. Simplify the units of measure and perform the division
As you may have noticed, the unit of measurement "ounces" appears twice: in the numerator of the first fraction and in the denominator of the second. By multiplying the two fractions involved and the relative units of measurement, you can eliminate the "ounces" from the calculation. The only unit of measurement that will remain will be the "grams" which is the final one of the conversion. At this point, to obtain the final result, all you have to do is perform the division.
In the example problem we can eliminate the "ounces" from the calculation since they appear in the numerator of the first fraction and in the denominator of the second. To get the final value you will simply have to perform the following calculation: 1, 23/0, 035 = 35, 14 g.
Step 4. To perform other types of conversions modify the conversion factor so that the units of measure to be converted can be simplified correctly
The main advantage of using a conversion factor is that you can perform multiple conversions simultaneously. All that is needed is to use the method described in the first steps of this section and the appropriate conversion factors, so that all units of measurement, except the final one, can be simplified to each other. Here are some examples:
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Assume for a moment that you have forgotten how ounces are converted to grams, but you know that a pound contains 16 ounces, that 2.2 pounds equals one kilogram, and that the latter is equal to 1,000 grams. Having this information available, you can obtain all the conversion factors you need and convert ounces into grams.
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- 1.23 ounces / 1 × 1 lb / 16 ounces × 1 kg / 2.2 lbs × 1,000 g / 1 kg
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All units of measurement indicated in the calculation, except grams, can be eliminated. At this point all you need to do is perform the calculations:
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- = (1, 23 × 1,000) / (16 × 2, 2 & times) = 1,230 / 35, 2 = 34, 94 g (practically the same result obtained in the previous step)
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Advice
- To convert a value from grams to ounces, simply divide it by the same coefficient: 28, 35.
- The standard symbol for ounces is "oz". It seems that this abbreviation derives from the Italian word "onzo".
