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Finding the Fourth Proportional to 709.08, 978.04 and 499.69

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Solution

The fourth proportional to 709.08, 978.04 and 499.69 is: 689.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    709.08 : 978.04 = 499.69 : x
  2. Step 2: Convert to fraction form
    709.08/978.04 = 499.69/x
  3. Step 3: Cross multiply
    709.08x = 978.04 × 499.69
  4. Step 4: Simplify right side
    709.08x = 488,716.81
  5. Step 5: Solve for x
    x = 488,716.81/709.08
  6. Step 6: Final answer
    x = 689.23

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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.