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Finding the Fourth Proportional to 673.65, 929.31 and 390.05

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Solution

The fourth proportional to 673.65, 929.31 and 390.05 is: 538.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    673.65 : 929.31 = 390.05 : x
  2. Step 2: Convert to fraction form
    673.65/929.31 = 390.05/x
  3. Step 3: Cross multiply
    673.65x = 929.31 × 390.05
  4. Step 4: Simplify right side
    673.65x = 362,470.77
  5. Step 5: Solve for x
    x = 362,470.77/673.65
  6. Step 6: Final answer
    x = 538.07

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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.