For dissimilar fractions in addition and subtraction, find the LCD and convert the fractions to similar form.

In multiplication, you just multiply the numerator and the denominator accordingly.

In division, you reciprocate the second term and multiply it as you would.

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You can add fractions if the denominators are the same and simply add the numerators. If fractions have  different denominators, determine LCD so that you ca express each fraction in equivalent form.

Subtracting fractions is the same as adding, your calculation need to have the same denominator and need to determine LCD.

To multiply fraction is carried by multiplying all the numerators together and all the denominators together. Sometimes multiplying fractions can be simplified by dividing both numerator and denominator by the same number.

Dividing Fraction, just simply invert and multiply.