How do I find the missing number in the following proportion? ___: 8 = 12:32

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Answer 1 · 2017-11-20T22:34:32

The missing number is $3$ $3$ .

Think like this:

$\frac{x}{8} = \frac{12}{32}$ $x/8 = 12/32$

Cross multiply

$32 x = 96$ $32x = 96$

Divide both sides by $32$ $32$ to get

$x = 3$ $x = 3$

Answer 2 · 2017-11-20T22:43:49

See a solution process below:

We can call the number we are looking for $n$ $n$

We can now rewrite this problem as:

$\frac{n}{8} = \frac{12}{32}$ $n/8 = 12/32$

We can multiply each side of the equation by $8$ $color(red)(8)$ to solve for $n$ $n$ while keeping the equation balanced:

$8 \times \frac{n}{8} = 8 \times \frac{12}{32}$ $color(red)(8) xx n/8 = color(red)(8) xx 12/32$

$cancel(color(red)(8)) xx n/color(red)(cancel(color(black)(8))) = cancel(color(red)(8)) xx 12/(color(red)(cancel(color(black)(32)))4)$

$n = 12/4$

$n = 3$