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Finding the Fourth Proportional to 420.42, 577.08 and 372.78

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Solution

The fourth proportional to 420.42, 577.08 and 372.78 is: 511.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.42 : 577.08 = 372.78 : x
  2. Step 2: Convert to fraction form
    420.42/577.08 = 372.78/x
  3. Step 3: Cross multiply
    420.42x = 577.08 × 372.78
  4. Step 4: Simplify right side
    420.42x = 215,123.88
  5. Step 5: Solve for x
    x = 215,123.88/420.42
  6. Step 6: Final answer
    x = 511.69

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.