How do you solve #0.1d-0.03+0.3d=0.25#?

1 Answer
Jan 7, 2016

#d=7/10=0.7#

Explanation:

Yuo can thinking that:

#d=x#

then to find d you have to solve the equation

#0.1x-0.03+0.3x=0.25#

Addiction the terms in x and move the not x terms on the right of =

#0.4x=0.25+0.03#

#0.4x=0.28#

Converting the decimal number in fractions

#4/10x=28/100#

Finding the

#m.c.d. =100#

#(10*4x)/100=28/100#

#(40x)/100=28/100#

#40x=28#

#x=28/40#

Semplyfing fraction by 4

#x=cancel(28)^7/cancel(40)_10=7/10#

Then:

#x=d=7/10#