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Finding the Fourth Proportional to 787.86, 1,087.79 and 508.77

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Solution

The fourth proportional to 787.86, 1,087.79 and 508.77 is: 702.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.86 : 1,087.79 = 508.77 : x
  2. Step 2: Convert to fraction form
    787.86/1,087.79 = 508.77/x
  3. Step 3: Cross multiply
    787.86x = 1,087.79 × 508.77
  4. Step 4: Simplify right side
    787.86x = 553,432.37
  5. Step 5: Solve for x
    x = 553,432.37/787.86
  6. Step 6: Final answer
    x = 702.45

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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.