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Finding the Fourth Proportional to 804.72, 1,207.80 and 512.40

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Solution

The fourth proportional to 804.72, 1,207.80 and 512.40 is: 769.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.72 : 1,207.80 = 512.40 : x
  2. Step 2: Convert to fraction form
    804.72/1,207.80 = 512.40/x
  3. Step 3: Cross multiply
    804.72x = 1,207.80 × 512.40
  4. Step 4: Simplify right side
    804.72x = 618,876.72
  5. Step 5: Solve for x
    x = 618,876.72/804.72
  6. Step 6: Final answer
    x = 769.06

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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.