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Finding the Fourth Proportional to 646.21, 969.47 and 299.78

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Solution

The fourth proportional to 646.21, 969.47 and 299.78 is: 449.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.21 : 969.47 = 299.78 : x
  2. Step 2: Convert to fraction form
    646.21/969.47 = 299.78/x
  3. Step 3: Cross multiply
    646.21x = 969.47 × 299.78
  4. Step 4: Simplify right side
    646.21x = 290,631.58
  5. Step 5: Solve for x
    x = 290,631.58/646.21
  6. Step 6: Final answer
    x = 449.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.