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Finding the Fourth Proportional to 556.20, 835.10 and 420.20

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Solution

The fourth proportional to 556.20, 835.10 and 420.20 is: 630.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    556.20 : 835.10 = 420.20 : x
  2. Step 2: Convert to fraction form
    556.20/835.10 = 420.20/x
  3. Step 3: Cross multiply
    556.20x = 835.10 × 420.20
  4. Step 4: Simplify right side
    556.20x = 350,909.02
  5. Step 5: Solve for x
    x = 350,909.02/556.20
  6. Step 6: Final answer
    x = 630.90

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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.