14. The ratio $a: b: c=2: 3: 4$. The ratio $c: d: e=3: 4: 5$. What is the ratio $a: e$ ?
A $1: 10$
B $1: 5$
C $3: 10$
D $2: 5$
E $1: 2$
Solution
C

The ratio $a: b: c=2: 3: 4=6: 9: 12$.
The ratio $c: d: e=3: 4: 5=12: 16: 20$.
Therefore the ratio $a: b: c: d: e=6: 9: 12: 16: 20$. Hence the ratio $a: e=6: 20=3: 10$.