Question 1199403: say you divide 75.92 by 1.3
I multiplied 75.92 by 100 so it becomes 7592
I also multiplied 1.3 by 10 to get a whole number , 13
Then, I divided the whole numbers (7592 division 13 ) and got 584
Now, I divided 584 by 10 and 100 since I want to reverse the multiplication I did before and so I get : 0.584
But that is not the correct answer . So , then How do I work such problems please?
Found 5 solutions by josgarithmetic, MathTherapy, math_tutor2020, greenestamps, ikleyn:
Answer by josgarithmetic(39617)   (Show Source):
Answer by MathTherapy(10552)  (Show Source):
You can put this solution on YOUR website! say you divide 75.92 by 1.3
I multiplied 75.92 by 100 so it becomes 7592
I also multiplied 1.3 by 10 to get a whole number , 13
Then, I divided the whole numbers (7592 division 13 ) and got 584
Now, I divided 584 by 10 and 100 since I want to reverse the multiplication I did before and so I get : 0.584
But that is not the correct answer . So , then How do I work such problems please?
You did it WRONG. He also did it WRONG, although his answer is correct!
STEP 1: Turn the DIVISOR, 1.3 into a WHOLE NUMBER. This is done by MOVING the decimal point ONE (1) place to the right.
In this case the DIVISOR, 1.3 becomes 13.
STEP 2: The SAME number of places you move the decimal point in the DIVISOR, the same number of places you move the
decimal point in the DIVIDEND. As such, the DIVIDEND, 75.92 becomes 759.2
STEP 3: You now DIVIDE 759.2 by 13. You should get: 58.4.
That's IT!!! Nothing MORE, Nothing LESS!!
Answer by math_tutor2020(3817) (Show Source):
Answer by greenestamps(13200)  (Show Source):
You can put this solution on YOUR website!
You made the problem more complicated than it needs to be by multiplying one of the numbers by 100 and the other by 10 -- presumably to make them both whole numbers.
But doing that makes arriving at the correct answer more difficult -- dividing the two resulting whole numbers gives the wrong answer, because you didn't multiply the two original numbers by the same number.
If you want to keep the decimal places in your calculations, then you need to multiply both of the given numbers by the same number.
The other tutors who responded showed different ways to do the problem correctly. You can do either 759.2 divided by 13, or 7592 divided by 130.
But another (probably easier) method is to ignore the decimal points completely in your actual calculation.
Divide 7592 by 13 (which is what you did eventually) to get 584. Those are the correct digits in the answer; but you need to determine where the decimal point goes.
The original problem has you dividing 75.92 by a number a bit greater than 1, so the result should be something a bit less than 75.92.
Obviously neither the "584" itself doesn't satisfy that condition; nor does your answer of "0.584". The only reasonable answer -- a number "a bit less than" 75.92 with digits "584" -- is 58.4.
Answer by ikleyn(52786)  (Show Source):
You can put this solution on YOUR website! .
This problem invites to find an error in the somebodies' incorrect calculations.
As a rule, such problems teaches NOTHING and are used by incompetent teachers simply to kill
the time during a lesson, when such "teachers" don't know how to use this time productively.
From the very beginning you make non-equivalent " prohibited " transformations,
and then make " blue eyes " and ask what is wrong.
As I said, such problems do teach NOTHING and only serve to kill the time.
Run from the teachers who give such assignments, as fast and as far as you can.
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