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Finding the Fourth Proportional to 787.80, 1,087.68 and 508.76

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Solution

The fourth proportional to 787.80, 1,087.68 and 508.76 is: 702.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.80 : 1,087.68 = 508.76 : x
  2. Step 2: Convert to fraction form
    787.80/1,087.68 = 508.76/x
  3. Step 3: Cross multiply
    787.80x = 1,087.68 × 508.76
  4. Step 4: Simplify right side
    787.80x = 553,360.09
  5. Step 5: Solve for x
    x = 553,360.09/787.80
  6. Step 6: Final answer
    x = 702.41

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1.5x scale

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.