Hello, I need did a subtraction problem with mixed numbers by converting the LCD of the denominator.
However, when I went to Algebra.help they did the problem by converting the mixed problem to an improper fraction and then worked it that way.
However, I know that the answers should be the same.
Please check my method. I don't want to convert the whole numbers to mixed.
9 10/12 minus 5 6/7
9 70/84 minus 5 72/84
equals 4 2/84
reduced to 4 1/42
Algebra help say the answer is:
3 41/42
Your algebra help is correct.
Your problem is in your second step. You can't take 72 from 70. Therefore, you need to change 9 70/84 to 8 154/84.
8 154/84 - 5 72/84 = 3 82/84 = 3 41/42
How did you change 9 70/84 to 8 154/84?
Subtract 1 frp, 9 and add to the fraction.
1 = 84/84
23/6 convert to a mix number
To subtract mixed numbers with different denominators, you can convert the mixed numbers to improper fractions and then find a common denominator. Your method of finding a common denominator by converting the LCD of the denominators is correct. However, it seems that there might be an error in your calculations when subtracting the fractions. Let's go step by step to identify the mistake:
Step 1: Convert the mixed numbers to improper fractions:
9 10/12 = (9 * 12 + 10) / 12 = 118/12
5 6/7 = (5 * 7 + 6) / 7 = 41/7
Step 2: Find a common denominator:
The denominators are already the same, 12 and 7, so we don't need to make any conversions.
Step 3: Subtract the fractions:
118/12 - 41/7
To subtract fractions, they need to have the same denominator. In this case, we can use the denominator 84 because it is the least common multiple (LCM) of 12 and 7.
Multiplying the first fraction (118/12) by 7/7 and the second fraction (41/7) by 12/12, we have:
(118 * 7) / (12 * 7) - (41 * 12) / (7 * 12)
826/84 - 492/84
(826 - 492) / 84
334/84
Step 4: Simplify the fraction:
To simplify the fraction, we can divide the numerator and denominator by their greatest common divisor (GCD) which is 2 in this case:
334/84 = (2 * 167) / (2 * 42) = 167/42
Finally, convert the improper fraction back to a mixed number:
167/42 = 4 41/42
Therefore, the correct answer is 4 41/42, which matches the result given by Algebra.help.
There seems to be a mistake in your subtraction calculation. By correctly subtracting the fractions, you will arrive at the same answer as provided by Algebra.help, which is 3 41/42.