What is the solution to the proportion #x/(12-x)=5/15#?

1 Answer
Apr 29, 2015

Solving this would require cross multiplication

we are given
#x/(12-x)# #=# #5/15#

on cross multiplying:
15 is taken to the L.H.S numerator and (12 - x) is taken to R.H.S numerator

we get:
15#x# #=# 5(12 - #x#)
15#x# #=# 60 - 5#x#
20#x# #=# 60

#x# #=# 3

so our proportion is:

#3/9# #=##5/15#

note: on solving both fractions we get equal value of 0.33 on both sides thus they are in proportion as L.H.S #=# R.H.S