Question 1

Why not always use the least common denominator?

Accepted Answer

The LCD keeps numbers smaller, which matters by hand. The product b·d always works, and reducing at the end gives the same final answer.

Question 2

How do I add mixed numbers like 2 1/3 + 1 1/4?

Accepted Answer

Convert to improper fractions first (7/3 + 5/4 = 43/12), then convert back if you want: 3 7/12.

Question 3

How do I calculate with three or more fractions?

Accepted Answer

Apply the operation two at a time, following the usual order of operations: multiplication and division before addition and subtraction.

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