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Finding the Fourth Proportional to 425.04, 640.86 and 389.04

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Solution

The fourth proportional to 425.04, 640.86 and 389.04 is: 586.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.04 : 640.86 = 389.04 : x
  2. Step 2: Convert to fraction form
    425.04/640.86 = 389.04/x
  3. Step 3: Cross multiply
    425.04x = 640.86 × 389.04
  4. Step 4: Simplify right side
    425.04x = 249,320.17
  5. Step 5: Solve for x
    x = 249,320.17/425.04
  6. Step 6: Final answer
    x = 586.58

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.