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Finding the Fourth Proportional to 420.84, 628.20 and 372.78

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Solution

The fourth proportional to 420.84, 628.20 and 372.78 is: 556.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.84 : 628.20 = 372.78 : x
  2. Step 2: Convert to fraction form
    420.84/628.20 = 372.78/x
  3. Step 3: Cross multiply
    420.84x = 628.20 × 372.78
  4. Step 4: Simplify right side
    420.84x = 234,180.40
  5. Step 5: Solve for x
    x = 234,180.40/420.84
  6. Step 6: Final answer
    x = 556.46

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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.