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Finding the Fourth Proportional to 723.80, 1,085.71 and 520.10

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Solution

The fourth proportional to 723.80, 1,085.71 and 520.10 is: 780.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    723.80 : 1,085.71 = 520.10 : x
  2. Step 2: Convert to fraction form
    723.80/1,085.71 = 520.10/x
  3. Step 3: Cross multiply
    723.80x = 1,085.71 × 520.10
  4. Step 4: Simplify right side
    723.80x = 564,677.77
  5. Step 5: Solve for x
    x = 564,677.77/723.80
  6. Step 6: Final answer
    x = 780.16

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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.