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Finding the Fourth Proportional to 420.03, 628.83 and 378.11

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Solution

The fourth proportional to 420.03, 628.83 and 378.11 is: 566.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.03 : 628.83 = 378.11 : x
  2. Step 2: Convert to fraction form
    420.03/628.83 = 378.11/x
  3. Step 3: Cross multiply
    420.03x = 628.83 × 378.11
  4. Step 4: Simplify right side
    420.03x = 237,768.48
  5. Step 5: Solve for x
    x = 237,768.48/420.03
  6. Step 6: Final answer
    x = 566.08

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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.