Question

learn with an example
find the number that makes the ratio equivalent to 3:9.
6:

Explanation:

Step1: Simplify the original ratio

The ratio \( 3:9 \) can be simplified by dividing both parts by their greatest common divisor, which is 3. So, \( \frac{3}{3}:\frac{9}{3}=1:3 \).

Step2: Find the missing number

We have the ratio \( 6:\text{[missing number]} \) which should be equivalent to \( 1:3 \). Let the missing number be \( x \). Then, \( \frac{6}{x}=\frac{1}{3} \) (since the ratios are equivalent, the fractions formed by them are equal). Cross - multiplying gives us \( x = 6\times3=18 \). We can also think in terms of the multiplier. From 3 to 6, we multiply by 2. So, we multiply the second part of the ratio \( 3:9 \) by 2 as well. \( 9\times2 = 18 \).

Answer:

18