Unit conversions involving Pascals

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jbriggs444 said:
Online converters work. Just have to use the right units. I Googled "convert square millimeters to square meters". Without leaving the Google page, a converter was displayed. I keyed in 1963.5.
View attachment 255555

Good nit saying that it s an area value it was a mistake
 
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A.T. said:
Use the one for which you have the required variables.

Yeah and is it that you multiply first or work the division separated and the multiply the results ?
 
chriscarson said:
Yeah and is it that you multiply first or work the division separated and the multiply the results ?
Multiply what by what or work what division? Are you seriously asking how to evaluate ##\frac{a}{b} \times \frac{c}{d}##?
 
jbriggs444 said:
Multiply what by what or work what division? Are you seriously asking how to evaluate ##\frac{a}{b} \times \frac{c}{d}##?

Yes is that so basic ?
 
chriscarson said:
Yes is that so basic ?
Here in the U.S. we are taught to add and multiply fractions at about age eight.

For ##\frac{a}{b} \times \frac{c}{d}## there are many ways to evaluate the result and get the same right answer. The canonical "right" way is to:

1. Divide a by b giving the result ##\frac{a}{b}##.
2. Divide c by d giving the result ##\frac{c}{d}##.
3. Multiply those two results together.

Another way is to:

1. Multiply a by c giving the result ##ac##.
2. Multiply b by d giving the result ##bd##.
3. Divide the result from 1) by the result from 2).

It is a rule of arithmetic and of real algebra that$$\frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd}$$

One rule of algebra that they didn't teach us until age 16 or so was that putting two variable names side by side ("juxtaposition") is a notation that conventionally means "multiply them together".

[As it turns out my first exposure to the juxtaposition notation was in a standardized test -- they tested on it before my school had ever presented the content. It is over 40 years later now and that incident still cheeses me off]
 
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jbriggs444 said:
Here in the U.S. we are taught to add and multiply fractions at about age eight.

For ##\frac{a}{b} \times \frac{c}{d}## there are many ways to evaluate the result and get the same right answer. The canonical "right" way is to:

1. Divide a by b giving the result ##\frac{a}{b}##.
2. Divide c by d giving the result ##\frac{c}{d}##.
3. Multiply those two results together.

Another way is to:

1. Multiply a by c giving the result ##ac##.
2. Multiply b by d giving the result ##bd##.
3. Divide the result from 1) by the result from 2).

It is a rule of arithmetic and of real algebra that$$\frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd}$$

One rule of algebra that they didn't teach us until age 16 or so was that putting two variable names side by side ("juxtaposition") is a notation that conventionally means "multiply them together".

[As it turns out my first exposure to the juxtaposition notation was in a standardized test -- they tested on it before my school had ever presented the content. It is over 40 years later now and that incident still cheeses me off]

Yeah finally is that what I thought but I m finding so many obstacles that I want to be 100% in every tiny thing .