Addition and subtraction of different denominator fractions, 10 parallel detachments,

Differing denominators. Fraction addition and subtraction, in simple terms, is to find the least common multiple of the denominator.

Through, add the molecules, reduce the fraction, and get the result.

The figure below shows 10 off-form calculations.

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The specific calculation steps are as follows:

1. Find the least common multiple of the two denominators.

2. Divide the least common multiple by the denominator respectively, and expand the corresponding multiple of the grave of the two fractions at the same time.

3. Take the least common multiple as the denominator, and add or subtract the numerators.

4. Get the final result, and make an offer to get points.

Solve the following equations. (2 points per question) 12x x = 45150% x off-line calculation. (If you can make a simple calculation, you should make a simple calculation.) (3 marks per question) (1245.)

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The addition and subtraction of fractions with different denominators is simply to find the least common multiple of the denominator, pass the fraction, add the numerators, reduce the fraction, and get the result.

The figure below shows 10 example problems for off-form calculations.

The specific calculation steps are as follows:

1. Find the least common multiple of the two denominators.

2. Divide the least common multiple by the denominator respectively, and expand the corresponding multiple at the same time to the grave of the numerator of the two wax acacia fractions.

3. Take the least common multiple as the denominator, and add or subtract the numerators.

4. Get the final result, and make an offer to get points.

When the fraction of the different denominator is added or subtracted, the score of the different denominator is calculated according to the calculation method of the addition and subtraction of the fraction of the same denominator.

General scoring method: 1. Find the least common multiple of the denominator of the original fractions;

2. According to the basic nature of the fraction, the original fraction is converted into a fraction with this least common multiple as the denominator.

Example: Calculate 5 6 + 7 8

The least common multiple of 6 and 8 is 24

24 is 4 times larger than 6, i.e., 5 6 = 20 2424 is 3 times larger than 8, and 7 8 = 21 241, the step method of fraction reduction.

1) Decompose the numerator and denominator into factors.

2) Find the common factor of the numerator and denominator.

3) Eliminate the non-zero common factor.

2. Multiplication of fractions.

1) The fraction is multiplied by an integer, the denominator remains unchanged, the numerator is multiplied by an integer, and finally the offer fraction that can be reduced.

2) Multiply fractions by fractions, multiply numerators by numerators, multiply denominators by denominators, and finally offer fractions that can be reduced.

The fractional addition and subtraction method of heterodenominator requires that the denominator be converted into a common denominator, and then the numerator is added and subtracted separately, and the result is reduced to the simplest fraction form after the most mountain worm. For example, let's say you want to calculate 1 3 + 1 4, you first need to find their least common multiple, which is 12. Then 1 3 and 1 4 are reduced to the same denominator, i.e.:

1 3 = 4 121 4 = 3 12 Now, add up their numerators to get: 4 12 + 3 12 = 7 12 The final result is 7 12, if you need to make it into the simplest fraction form, you can divide the numerator and denominator by their greatest common factor at the same time to get the slag best simplest fraction 2 3. Similarly, if you want to calculate the subtraction of fractions, such as 3 5 - 1 7, you need to find their least common multiples first, then convert them to the same denominator, and then do the subtraction operation.

Hope it helps.

Kiss! Addition and subtraction of fractions with different denominators refers to the method of adding and subtracting two or more fractions with different denominators. The basic steps are as follows:

The denominator of each fraction is divided, i.e. they are reduced to the same denominator. For each co-fraction after the general fraction, their numerators are recalculated according to the denominator after the general fraction. After obtaining the general fraction, you can operate according to the ordinary rules of addition and subtraction of fractions, that is, add and subtract their numerators, and keep the denominator unchanged.

After addition and subtraction, if you get a band fraction, you should convert it to a false fraction and try to reduce the result to a fraction. For example, to add the fractions 2 3 and 5 8 by dividing 2 3 and 5 8 together, you get two fractions with a denominator of 24:

16 24 and 15 24. According to the denominator after the general fraction, the numerator is recalculated, and the following is obtained: 2 3 = 16 24, 5 8 = 15 24.

Perform the addition operation to give 16 24 + 15 24 = 31 24. Since 31 is greater than 24, the hand god can convert it to a band fraction, giving 1 7 24. It should be noted that for subtraction, the numerator of the second fraction in the operand needs to be taken as the opposite number, and then calculated according to the method of addition operation.