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Finding the Fourth Proportional to 646.15, 970.21 and 404.20

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Solution

The fourth proportional to 646.15, 970.21 and 404.20 is: 606.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.15 : 970.21 = 404.20 : x
  2. Step 2: Convert to fraction form
    646.15/970.21 = 404.20/x
  3. Step 3: Cross multiply
    646.15x = 970.21 × 404.20
  4. Step 4: Simplify right side
    646.15x = 392,158.88
  5. Step 5: Solve for x
    x = 392,158.88/646.15
  6. Step 6: Final answer
    x = 606.92

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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.