#color(blue)("Establishing the ratio format and content")#
1 microgram #= 1xx10^(-6)" grams " larr " 1 millionth of 1 gram"#
#color(white)(.)#
#color(red)("Using ratio")#
#("micrograms")/("grams") ->color(magenta)(1/(10^(-6))) -=("micrograms")/(2.45xx10^3)#
#color(white)(.)#
#color(red)("but "1/10^(-6) " is the same as "(10^6)/1)#
#color(white)(.)#
#("micrograms")/("grams") ->color(magenta)((10^6)/1) -=
("micrograms")/(2.45xx10^3)#
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("The calculation")#
#color(brown)((10^6)/1 -=("micrograms")/(2.45xx10^3))#
#color(white)(.)#
#color(red)("Multiply bot sides by "color(blue)(2.45xx10^3))#
#color(white)(.)#
#color(brown)((10^6)/1 color(blue)(xx2.45xx10^3) " "=" micrograms "xx(color(blue)(cancel(2.45xx10^3)))/(cancel(2.45xx10^3)) )#
#color(white)(.)#
#"micrograms "=2.45xx10^3xx10^6" "=" "2.45xx10^9#