Home » Mathematics » If  x : y = (frac{1}{4} : frac{3}{8}) and y : z = (frac{1}{3} :…

If  x : y = (frac{1}{4} : frac{3}{8}) and y : z = (frac{1}{3} :…

If  x : y = (frac{1}{4} : frac{3}{8}) and y : z = (frac{1}{3} : frac{4}{9}), find x : z

  • A.
    2:3
  • B.
    3:4
  • C.
    3:8
  • D.
    1:2
Correct Answer: Option D
Explanation

(frac{x}{y}) = (frac{1}{4} div frac{3}{8}) = (frac{1}{4} times frac{8}{3}) = (frac{2}{3})

(frac{y}{z}) = (frac{1}{3} div frac{4}{9}) = (frac{1}{3} times frac{9}{4}) = (frac{3}{4})

But,

x = (frac{2}{5}T_1), y = (frac{3}{5}T_1)

y = (frac{3}{7}T_2), z = (frac{4}{7}T_2)

Using y = y

(frac{3}{5}T_1) = x = (frac{3}{7}T_2)

 (frac{T_1}{T_2}) = (frac{3}{7}) x (frac{5}{3}) = (frac{15}{21})

(T_1 = 15) and (T_2 = 21)

Thus , x = (frac{2}{5}) x 15 = 6

y = (frac{3}{5}) x 15 = 9

y = (frac{3}{7}) x 21 = 9

z = (frac{4}{7}) x 21 = 12

Hence; x : z = 6 : 12

= 1 : 2