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Finding the Fourth Proportional to 630.59, 869.63 and 420.66

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Solution

The fourth proportional to 630.59, 869.63 and 420.66 is: 580.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.59 : 869.63 = 420.66 : x
  2. Step 2: Convert to fraction form
    630.59/869.63 = 420.66/x
  3. Step 3: Cross multiply
    630.59x = 869.63 × 420.66
  4. Step 4: Simplify right side
    630.59x = 365,816.45
  5. Step 5: Solve for x
    x = 365,816.45/630.59
  6. Step 6: Final answer
    x = 580.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.