SOLUTION: i can not figure out 7 4/5 times 2 1/3. could you please help me

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Question 566340: i can not figure out 7 4/5 times 2 1/3. could you please help me

Found 2 solutions by Tias_411, bucky:
Answer by Tias_411(14) About Me  (Show Source):
You can put this solution on YOUR website!
its best to convert them to improper fractions first.. 7 4/5= 39/5 and 2 1/3= 7/3. then you just multiply the numerators and denominators. 39*7 and 5*3.. that gives you 273/15. then you turn that back into a mixed number.. giving you an answer of 18 3/15 which is also equal to 18 1/5 in lowest terms.. i think..

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
To do this multiplication in fractional form, first convert the two numbers to improper fractions. We'll do that one at a time.
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First, let's convert 7+%26+4%2F5 to an improper fraction. Do that by multiplying the denominator 5 times the whole number 7 to get 35 and then add the 4 to the 35 to get an answer of 39. The 39 is then placed over the denominator 5 to get the improper fraction 39%2F5.
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Note that you can check this by dividing 5 into 39 and you get 7 with a remainder of 4.
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Next let's convert the 2+%26+1%2F3 into an improper fraction. Use the same process as we did earlier. Multiply the denominator 3 times the whole number 2 to get 6 and then add the numerator 1 to the 6 to get 7. So the improper fraction that results is 7%2F3. Check by dividing 3 into 7 and you get 2 with a remainder 1 (the whole number and the numerator).
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Now we multiply the two improper fractions as follows:
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%2839%2F5%29%2A%287%2F3%29
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We multiply the two numerators together. 39 times 7 gives a product of 273.
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Then we multiply the two denominators together. 5 times 3 is 15.
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The answer we got for the product of the two improper fractions is 273%2F15 as shown below:
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%287+%26+4%2F5%29%2A%282+%26+1%2F3%29=+273%2F15
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Now we can convert this Improper fraction (meaning the numerator is bigger than the denominator) back into a mixed number by dividing 15 into 273. 15 goes into 273 18 times with a remainder of 3. So the answer 273 divided by 15 results in the following mixed number:
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18+%26+3%2F15
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But the 3 over 15 can be reduced to 1 over 5 by dividing both the numerator 3 and the denominator 15 by 3.
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So the final answer for the multiplication is 18+%26+1%2F5
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Hope this helps you understand the following points:
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1. You convert a mixed number (a whole number and a fraction) to an improper number (single fraction with a numerator bigger that its denominator) by multiplying the denominator of the fraction times the whole number, then adding the numerator of the fraction, and then placing the result over the denominator.
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2. To multiply two mixed numbers, convert both of those two numbers to improper fractions.
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3. Multiply the two numerators of the improper fractions together and get the numerator product.
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4. Multiply the two denominators of the improper fractions together and get the denominator product.
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5. Form a new fraction consisting of the numerator product over the denominator product.
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6. Convert the answer back to a mixed number by dividing the denominator product into the numerator product to get the whole number part. Then place the remainder over the denominator product to get the fractional part and reduce it if possible.
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