Question

a picture is enlarged proportionally. original picture is 5cm long and 3cm wide.if the new.larger picture is 12 cm wide what is its length

Answer 1

Answer :-
_____________________________

Let us review the concept of proportion

Proportion is the simplest form of fraction in which the the Two or more given quantity can be displayed
like 8 & 16 on proportion = 8/16 = 1/2 = 1:2

_______________________________
Now Provided

Enlargement is proportional
then the proportion
= length : width (in simplest term)
= 5 : 3
As this can not be reduced
constant proportion = 5 : 3

Now enlarged width = 12 cm

then
Enlarged length : Enlarged width = 5 : 3

Let the enlarged length be X
then
$\frac{x}{12} = \frac{5}{3} \\ \\ = > 3x = 60 \\ \\ = > x = 20$
So enlarged length = 20 cm