1) Set up proportions for the ratios:
[tex] \frac{5}{2} = \frac{x}{4} [/tex]
Cross multiply the fractions:
[tex]2x = 20[/tex]
Divide both sides by 2 to get x by itself.
[tex]x = 10[/tex]
5 to 2 is equal to 10 to 4.
------------
2) Set up proportions for the ratios:
[tex] \frac{14}{21} = \frac{x}{15} [/tex]
Cross multiply the fractions:
[tex]21x = 210[/tex]
Divide both sides by 21 to get x by itself:
[tex]x = 10[/tex]
14 to 21 is equal to 10 to 15.
------------
OPTIONAL:
To make 2) easier to solve, simplify 14 to 21.
[tex] \frac{14}{21} / \frac{7}{7} = \frac{2}{3} [/tex]
Then, continue with the problem as described above:
[tex]\frac{2}{3} = \frac{x}{15}[/tex]
[tex]3x = 30[/tex]
[tex]x = 10[/tex]
