How wide is an airport runway that has an area of ½ square mile, if it is ¾ of a mile long?

a = lw

For a rectangular airport runway, as you described, the formula for area is "area equals length times width".

We already have the length and the width, so we can fill those is:

1/2 = 3/4w

Now we divide both sides by 3/4 to find w and isolate the variable:

1/2 ÷ 3/4 = w

To divide fractions, just multiple by the recipricol (numerator and denominator flip):

1/2 * 4/3 = w

To multiply, multiply the numerator and denominator of each:

1 * 4 = 4

2 * 3 = 6

So, 1/2 * 4/3 = 4/6 = 2/3 = w (width)

 $$\left({\frac{{\mathtt{3}}}{{\mathtt{4}}}}\right){\mathtt{\,\times\,}}{\mathtt{w}} = {\frac{{\mathtt{1}}}{{\mathtt{2}}}}$$

Now, re-arrange this to have w on one side by itself.

Im look for a good answer!

Thank you!

Both answers were good answers - do not be ungracious!

If you need more help ask for it politely!!