Schnitzel

I typed "1 astronomical unit / moon radius" into WolframAlpha and got 86,099.

Type them into WolframAlpha . com with a + sign between the whole number and its fraction. For example, 3 2/5 + 6 1/5 becomes (3+2/5) + (6+1/5) 3 - 1 8/12 becomes (3) - (1+8/12)

2a+ab=c FACTOR OUT a: a(2+b)=c DIVIDE BOTH SIDES BY (2+b): a=c/(2+b)

If X=A*B or X=A/B, then the uncertainty in X is: X*sqrt( ((uncertainty in A)/A)^2 + ((uncertainty in B/B))^2 )

Oops, I meant "1/R=1/2.3+1/x solve for R"

Type "1/R=1/2.3+1/x solve for x" into WolframAlpha . com and click "Show steps"

Yes, since the uncertainty of a product or quotient of two values depends on the uncertainty of each of those two values. (The more uncertain the values, the more uncertain the product or quotient of those values.)

3/(4N) = 3 MULTIPLY BOTH SIDES BY 4N: 3 = 3(4N) = 12N DIVIDE BOTH SIDES BY 12: N = 1/4

Google "mathematics of snowflakes". Here's a few interesting links: h t t p : / / g o o . g l / Q c 4 S 4 h t t p : / / g o o . g l / Y a H t z h t t p : / / g o o . g l / v w 1 z z