How do you find 25.8% of 4000?

3 Answers
Apr 14, 2018

#answer=1032#

Explanation:

consider we have to calculate #x%# of #y# so the sign of % after x shows that,
#x%=x/100#
& of represents the multiplication between those two terms, i.e.
x% of y=#x/100*y#
so, a/c to ques.
#25.8%of 4000#
=#25.8/100*4000=1032#

Apr 14, 2018

1032 is the answer

Explanation:

25.8%of 4000

#=25.8/100*4000#

#=1032#

Apr 14, 2018

Rather than just pumping out numbers I have demonstrated some tricks for doing some things in your head. Example: #xx4-># double and doubled again.

25.8% of 4000 =1032

Explanation:

#color(purple)("Initial bit of explaining percentage")#

Basically the symbol % means #xx1/100# including the multiply 'bit'

So #25.8% ->25.8xx1/100#

The mathematical equivalent of the word #color(red)("of")# in #25.8%color(red)(" of ")4000# is multiply. So we end up with:

#color(blue)(25.8color(white)("dd")color(green)(ubrace(%))color(white)("dd")color(red)(ubrace("of"))color(white)("ddd")4000)#

#color(blue)(25.8 color(white)("d")color(green)(xx1/100)color(white)("d.")color(red)(xx)color(white)("ddd")4000)#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(purple)("Answering the question")#

#25.8xx1/100xx4000color(white)("dddd")->color(white)("dddd")25.8xxcancel(4000)^(40)/cancel(100)^1#

#color(white)("ddddddddddddddddddd")->color(white)("dddd")ubrace(25.8xx10)xx4 #

#color(white)("ddddddddddddddddddd")->color(white)("dddddd")258color(white)("ddd")xx2xx2 #

#color(white)(1)516#
#ul(color(white)(1)516larr" Add")#
#1032#