SOLUTION: write the decimal expansions for these rational number. tell whether the expansions are terminating or repeating.
Find the rational number equivalents for these decimal expansio
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-> SOLUTION: write the decimal expansions for these rational number. tell whether the expansions are terminating or repeating.
Find the rational number equivalents for these decimal expansio
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Question 75572This question is from textbook algebra
: write the decimal expansions for these rational number. tell whether the expansions are terminating or repeating.
Find the rational number equivalents for these decimal expansions.
tell whether they are rational or irrational
simplify the following radicals. be sure to check your answers
This question is from textbook algebra
You didn't give any problems,
so I'll make some up. I hope they are
like the ones you were asked to solve.
All rational numbers expressed
as decimals will either terminate
or repeat a block of digits
forever. That's because in long
division all the remainders will
always be less than the divisor,
so sooner or later the remainder
will either be 0 or will be the
repeat of a remainder obtained
earlier.
write the decimal expansions for these
rational numbers. tell whether the
expansions are terminating or repeating.
#1. 9/32
Use long division:
.28125
32)9.00000
6 4
2 60
2 56
40
32
80
64
160
160
0
Terminating because the division
eventually has 0 remainder
#2. 15/22
Again use long division:
.6818
22)15.0000
13 2
1 80
1 76
40
22
18
This is a repeating decimal because the same
non-zero remainder 18 occurred twice in the
long division. These two 18's are indicated in
red above.
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Find the rational number equivalents for these
decimal expansions. tell whether they are
rational or irrational
#3. .185185185185···
Let N = .185185185185···
There are 3 digits in the repeating block
"185", so multiply by 103 or
1000
1000N = 185.185185185···
Now place the first equation underneath
and subtract the two equations
1000N = 185.185185185···
N = .185185185185···
999N = 185.000000000
999N = 185
N = 185/999
that reduces to
N = 5/27
This is RATIOnal because it is the
RATIO of two integers
#2. 2.9373737837···
Let N = 2.937373737···
There are 2 digits in the repeating block
"37", so multiply by 102 or
100
100N = 293.737373737···
Now place the first equation underneath
and subtract the two equations
100N = 293.737373737···
N = 2.93737373737···
99N = 290.800000000···
99N = 290.8
Clear of decimals by multiplying thru
by 10
990N = 2908
N = 2908/990
that reduces to
N = 1454/495
This is RATIOnal because it is the
RATIO of two integers
#3. .72772277722277772222···
This is IRRATIONAL because
there is no block of repeating
digits.
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simplify the following
radicals.
#4.
#5.
Edwin