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Finding the Fourth Proportional to 420.08, 626.15 and 387.27

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Solution

The fourth proportional to 420.08, 626.15 and 387.27 is: 577.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.08 : 626.15 = 387.27 : x
  2. Step 2: Convert to fraction form
    420.08/626.15 = 387.27/x
  3. Step 3: Cross multiply
    420.08x = 626.15 × 387.27
  4. Step 4: Simplify right side
    420.08x = 242,487.17
  5. Step 5: Solve for x
    x = 242,487.17/420.08
  6. Step 6: Final answer
    x = 577.25

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.