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Finding the Fourth Proportional to 785.90, 1,084.14 and 520.80

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Solution

The fourth proportional to 785.90, 1,084.14 and 520.80 is: 718.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.90 : 1,084.14 = 520.80 : x
  2. Step 2: Convert to fraction form
    785.90/1,084.14 = 520.80/x
  3. Step 3: Cross multiply
    785.90x = 1,084.14 × 520.80
  4. Step 4: Simplify right side
    785.90x = 564,620.11
  5. Step 5: Solve for x
    x = 564,620.11/785.90
  6. Step 6: Final answer
    x = 718.44

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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.