How do you arrange these from greatest to least: #- 5.7\bar97, -5.\bar797, -5.\bar79, -5.79\bar7, -5.797#?

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Answer 1 · 2017-09-24T05:45:55

#(5), (4), (2), (1)=(3)#

Greatest to smallest.

So let us write these numbers out a bit to determine which is largest.

#(1)=-5.797979797bar(97)#
#(2)=-5.79779779bar(779)#
#(3)=-5.797979797bar(97)#
#(4)=-5.7977777777bar(7)#
#(5)=-5.7970000000bar(0)#

so all of the numbers are the same until the ten thousands digit

#5.797# then number (3) and (1) have a 9 #-5.7979#

while (2) and (4) have a 7 #-5.7977#

and (5) has a 0 #-5.7970#

as such we can already arrange it in some order without looking further but we will need to look for differences between (3),(1) and (2),(4)

(3) and (1) repeat the same two digits over and over and as a result are the same.

(2) and (4)

(2) has a nine in the hundred thousand spot while (4) has a seven
#(2)=-5.79779#
#(4)=-5.79777#
as such 2 is smaller than 4 (since negative).

Now we have enough information to arrange in order.

#(5), (4), (2), (1)=(3)#

greatest to smallest.