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Finding the Fourth Proportional to 720.30, 1,081.35 and 478.38

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Solution

The fourth proportional to 720.30, 1,081.35 and 478.38 is: 718.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.30 : 1,081.35 = 478.38 : x
  2. Step 2: Convert to fraction form
    720.30/1,081.35 = 478.38/x
  3. Step 3: Cross multiply
    720.30x = 1,081.35 × 478.38
  4. Step 4: Simplify right side
    720.30x = 517,296.21
  5. Step 5: Solve for x
    x = 517,296.21/720.30
  6. Step 6: Final answer
    x = 718.17

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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.