Question

3 : 12 :: 15 : __________ step by step explain​

Answer 1

Answer:

3 : 12 :: 15 : 60

Step-by-step explanation:

Let the 4th term be x

then,

3 × x = 12 × 15

x = 180 / 3

x = 60

Answer 2

Answer:

Missing ratio is $60$ .

Step-by-step explanation:

To find : the missing value of proportion .

Given ratio :  $3: 12:: 15: ?$

Solution :

• As we can see that in the given ratio of proportion forth ratio is missing.  
• Let , missing ratio be $x$ .  We write as $3: 12:: 15: x$  

• In the proportion $3$ and $x$ are extremes while $12$ and $15$ are called as means .
• To find forth ratio we can write  $3: 12:: 15: x$  as,  $\frac{3}{12}=\frac{15}{x}$

• Transposing like terms we get,

     $\Rightarrow \quad x=\frac{15 \times 12}{3}$

• On simplifying we get,

     $\begin{array}{l}\Rightarrow x=5 \times 12 \\\Rightarrow x=60\end{array}$