Question

If a:b = 2:1, b:c = 3:5, c:d = 4:5 and e:d is 6:5, then find a:b:c:d:e.
a. 24:12:10:25:30
b. 24:12:20:25:30
c. 24:12:10:5:6
d. 24:12:10:25:6

Answer 1

the answer of this question will be option B

Answer 2

Given

a : b = 1 : 2

=>
$\frac{a}{b} = \frac{1}{2} \\ \\ = > b = 2a \\ \\ = > a = \frac{b}{2}$

b : c = 3 : 2

=>
$\frac{b}{c} = \frac{3}{2} \\ \\ = > c = \frac{2b}{3}$

d : c = 5 : 6

=>
$\frac{d}{c} = \frac{5}{6} \\ \\ = > d = \frac{5c}{6} \\ \\ = > d = \frac{5}{6} \times \frac{2b}{3} \\ \\ (since \: c = \frac{2b}{3} ) \\ \\ = > d = \frac{5}{3} \times \frac{b}{3} \\ \\ = > d = \frac{5b}{9}$



So we got, a = b/2, c = 2b/3 and d = 5b/9

Hence, a : b : c : d

= b/2 : b : 2b/3 : 5b/9

cancel b

=> 1/2 : 1 : 2/3 : 5/9

Take LCM

=> 9/18 : 18/18 : 12/18 : 10/18

cancel 18

=> 9 : 18 : 12 : 10