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Finding the Fourth Proportional to 1,209.92, 1,815.29 and 479.71

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Solution

The fourth proportional to 1,209.92, 1,815.29 and 479.71 is: 719.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,209.92 : 1,815.29 = 479.71 : x
  2. Step 2: Convert to fraction form
    1,209.92/1,815.29 = 479.71/x
  3. Step 3: Cross multiply
    1,209.92x = 1,815.29 × 479.71
  4. Step 4: Simplify right side
    1,209.92x = 870,801.29
  5. Step 5: Solve for x
    x = 870,801.29/1,209.92
  6. Step 6: Final answer
    x = 719.72

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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.