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Finding the Fourth Proportional to 840.08, 1,260.42 and 429.32

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Solution

The fourth proportional to 840.08, 1,260.42 and 429.32 is: 644.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.08 : 1,260.42 = 429.32 : x
  2. Step 2: Convert to fraction form
    840.08/1,260.42 = 429.32/x
  3. Step 3: Cross multiply
    840.08x = 1,260.42 × 429.32
  4. Step 4: Simplify right side
    840.08x = 541,123.51
  5. Step 5: Solve for x
    x = 541,123.51/840.08
  6. Step 6: Final answer
    x = 644.13

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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.