Question

Find the value of $x$ in the given proportion$:$

$0.9:0.6::x:3$

Answer 1

Step $1:$ To find the value of $x$ when the given number are in proportion

As we know that any four numbers $a,b,c$ and $d$ are said to be in proportion if and only if

$a:b::c:d$

$\frac{a}{b}=\frac{c}{d}$

Step $2:$ Given four numbers are in proportion $0.9:0.6::x:3$

Find the ratio of first and second number and equate it to the ratio of third and fourth number i.e.

$\frac{{\displaystyle 0.9}}{{\displaystyle 0.6}}=\frac{x}{{\displaystyle 3}}$

$\frac{{\displaystyle 9}}{{\displaystyle 6}}=\frac{x}{{\displaystyle 3}}$

$x=\frac{9\times 3}{6}$

$x=\frac{9}{2}$

$x=4.5$

Hence, the value of $x$ is $4.5$ when four numbers $0.9:0.6::x:3$ are in proportion.