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Question 1023129: Can you please solve this: Divide and simplify.
(-48/90) / (-32/72)
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! in general, a/b is the same as a * 1/b.
in other words, when you divide by something, it's the same thing as multiplying by the reciprocal of that something.
likewise, (a/b) / (c/d) is the same as (a/b) * (d/c).
same reason.
d/c is the reciprocal of c/d.
consequently, .....
(-48/90) / (-32/72) is the same as (-48/90) * (72/-32).
now a/-b is the same as -a/b is the same as -(a/b).
consequently, (-48/90) * (72/-32) is the same as -(48/90) * -(72/32).
now you know that a minus times a minus is equal to a plus, so .....
-(48/90) * -(72/32) is the same as (48/90) * (72/32).
now you also know that (48/90) * (72/32) is the same as (48 * 72) / (90 * 32) which is the same as (48/32) * (72/90).
48/32 can be reduced to 3/2, so the expression becomes (3 * 72) / (90 * 2).
3/90 can be reduced to 1/30, so the expression becomes (72) / (30 * 2).
72/2 can be reduced to 36/1, so the expression becomes 36 / 30.
36/30 can be reduced to 6/5.
since 6/5 can't be reduced any further, that's your solution.
you can confirm this solution is correct by doing the following in your scientific calculator that can handle parentheses.
enter exactly as shown: (-48/90) / (-32/72)
your calculator will tell you that the solution is 1.2.
enter 6/5 in your calculator and your calculator will tell you that the solution is 1.2.
since they both equal 1.2, they're equivalent, and so (-48/90) / (-32/72) = 6/5.
this confirms your solution is correct.
some calculators use a different - symbol to indicate a negative number.
if you use the - symbol for operations, when you wanted to indicate a negative number, you might get an incorrect response.
you might have to be a little bit careful about that.
my ti-84 plus is such a calculator.
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