Question

4.
If a : bis 3 : 4; b: cis 5:3 and a : d is 2 : 5, find the ratio of c: d.
1.3:5
2. 8: 15
3. 1: 5
4. 5:8
5.3:8​

Answer 1

Answer:

$\frac{a}{b} = \frac{3}{4} - (i) \\ \frac{b}{c} = \frac{5}{3} - (ii) \\ \frac{a}{d} = \frac{2}{5} - (iii) \\ \blue{\mathfrak{\underline{\large{Divide \: equation \: (iii) \: by \: (i)}}}:} \\ \frac{ \frac{a}{d} }{ \frac{a}{b} } = \frac{ \frac{2}{5} }{ \frac{3}{4} } \\ \frac{b}{d} = \frac{2 \times 4}{5 \times 3} = \frac{8}{15} \\ \frac{b}{d} = \ \frac{8}{15} - (iv) \\ \blue{\mathfrak{\underline{\large{Divide \: equation \: (iv) \: by \: (ii)}}}:} \\ \frac{ \frac{b}{d} }{ \frac{b}{c} } = \frac{ \frac{8}{15} }{ \frac{5}{3} } \\ \frac{c}{d} = \frac{8 \times 3}{15 \times 5} = \frac{8}{25} \\ \frac{c}{d} = \frac{8}{25} \\ \\ \red{\mathfrak{\underline{\large{Hope \: It \: Helps \: You }}}} \\ \green{\mathfrak{\underline{\large{Mark \: Me \: Brainliest}}}}$