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Finding the Fourth Proportional to 810.34, 1,118.55 and 478.72

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Solution

The fourth proportional to 810.34, 1,118.55 and 478.72 is: 660.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.34 : 1,118.55 = 478.72 : x
  2. Step 2: Convert to fraction form
    810.34/1,118.55 = 478.72/x
  3. Step 3: Cross multiply
    810.34x = 1,118.55 × 478.72
  4. Step 4: Simplify right side
    810.34x = 535,472.26
  5. Step 5: Solve for x
    x = 535,472.26/810.34
  6. Step 6: Final answer
    x = 660.80

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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.