math
posted by shay .
I need help. I have information on the metric system. I have to list things at home and grocery store that display metric units. I don't know if I quite understand. I am trying to understand the reason behind my answer. The metric units and measurements are lengh, mas(weight), time, temperature, area, volum, density and so on.
Examples:
Kelloggs Frosted Flakes because Net WT. 23 oz. (1lb. 7 oz.) (652g)
Zyrtec Allergy Medicine because 30 tablets 10 mg each
Is this right? Do I have the correct understanding?

Yes!!! :) You're doing great!
The metric measure for Frosted Flakes is 652 grams. The metric measure for the medicine is 10 milograms each. 
So a measurement for a room in my house for example:
A bath room 8X10 feet
or
A pillow 10X12 inches?
Would this be correct? 
Feet and inches are not part of the metric system. If you have a meter stick or tape measure, you could measure the bathroom in meters. You could measure the pillow in centimeters.

So for the pillow I can put 25X30 mm?
For the lenght, width I can use millimeter, centimeter, meter or kilometers? 
That's a mighty small pillow. 25 by 30 millimeters is about the size of a postage stamp. The pillow is about 25 by 30 centimeters. A standard bed pillow is about 45 by 65 centimeters.
Yes. Length is measured in millimeter, centimeter, meter or kilometers.
I urge you to get a ruler or meter stick or tape measure that has both metric and English measurments. 
A rancher has 200 feet of fencing with which to enclose two adjacent rectangular corrals. What measurements will produce a maximum enclosed area?

If you are to list them only, I think what you have done is ok. The frosted flakes box contains 23 oz which is the same as 1 lb 7 oz which is the same as 652 grams.
One Zyrtec tablet contains 10 mg of the active ingredient (each tables does not weigh 10 mg; usually fillers are added). 
For Zytrec the Quantity measured is the mass ("weight") and the unit will be milligrams. I am going by the information I have. Is this the correct understanding?

Yes, I think you are correct. I don't have a bottle at home so I can't check it out; however, I think the 10 mg is the active ingredient and not the weight of the individual tablet/capsule.

Yes you are right. It say cetirizine HCI/ antihistamine 10 mg tablets. But could I still use this as one of my answers?

certainly

Yes. Absolutely, use this as one of your examples of the metric system.