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Finding the Fourth Proportional to 810.30, 1,118.17 and 478.74

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Solution

The fourth proportional to 810.30, 1,118.17 and 478.74 is: 660.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.30 : 1,118.17 = 478.74 : x
  2. Step 2: Convert to fraction form
    810.30/1,118.17 = 478.74/x
  3. Step 3: Cross multiply
    810.30x = 1,118.17 × 478.74
  4. Step 4: Simplify right side
    810.30x = 535,304.72
  5. Step 5: Solve for x
    x = 535,304.72/810.30
  6. Step 6: Final answer
    x = 660.63

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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.