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Finding the Fourth Proportional to 646.79, 969.87 and 299.90

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Solution

The fourth proportional to 646.79, 969.87 and 299.90 is: 449.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.79 : 969.87 = 299.90 : x
  2. Step 2: Convert to fraction form
    646.79/969.87 = 299.90/x
  3. Step 3: Cross multiply
    646.79x = 969.87 × 299.90
  4. Step 4: Simplify right side
    646.79x = 290,867.56
  5. Step 5: Solve for x
    x = 290,867.56/646.79
  6. Step 6: Final answer
    x = 449.71

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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.