Question 1010656
1/2 inch=3 miles; Jerry measured 3 1/8 inches between two towns
on the map; what is the distance in miles between the two towns? 
<pre>

1/2 inch=3 miles; Jerry measured 3 1/8 inches

{{{matrix(1,13,

1/2,inch,is,to,3,miles,as,3&1/8,inches,is,to,X,miles)}}}

{{{matrix(1,7,

1/2,":",3,""="",3&1/8,":",X)}}}

{{{matrix(1,7,

1/2,"÷",3,""="",3&1/8,"÷",X)}}}

{{{matrix(1,7,

1/2,""*"",1/3,""="",3&1/8,""*"",1/X)}}}

{{{matrix(1,5,

1/6,""="",25/8,""*"",1/X)}}}

{{{matrix(1,3,

1/6,""="",25/(8X))}}}

Cross multiply

{{{matrix(1,3,

1*8X,""="",25*6)}}}

{{{matrix(1,3,

8X,""="",150)}}}

Divide both sides by 8

{{{matrix(1,3,

(8X)/8,""="",150/8)}}}

{{{matrix(1,3,

(cross(8)X)/cross(8),""="",18&3/4)}}}

{{{matrix(1,3,

X,""="",18&3/4)}}}

Answer: {{{matrix(1,2,18&3/4,miles)}}}

Edwin</pre>