How do you simplify #9.44\times 70.8#?

2 Answers
Mar 23, 2017

#668.352#

Explanation:

#9.44 xx 70.8#

#:.=9 44/100 xx 70 8/10#

#:.=944/100 xx 708/10#

#:.=668352/1000#

#:.=668.352#

Mar 24, 2017

#9.44 xx 70.8 = 668.352#

Explanation:

You can do long multiplication.

Ignore the decimal places for now:

#color(white)(...........)944#
#color(white)(...........)ul(color(blue)(7)0color(red)(8))#
#color(white)(..........)color(red)(7552)" "# multiply the top row by #color(red)(3)#
#color(white)(.......)ul(color(blue)(660800)" "# multiply the top row by #color(blue)(700)#
#color(white)(.......)ul(668352)" "#add the two rows

(There was no point in multiplying by the middle number, 0)

Now count how many decimal places there were altogether in the original numbers. There were #3# places.

#9color(red)(.44) xx 70color(red)(.8) = 668color(red)(.352)#

There must be the same number of places in the final answer.

As a final check, do a quick estimate of the size of the answer.
#9 xx 70 = 630#

An answer of #668# is in the right order of size.