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Finding the Fourth Proportional to 401.90, 554.49 and 318.75

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Solution

The fourth proportional to 401.90, 554.49 and 318.75 is: 439.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.90 : 554.49 = 318.75 : x
  2. Step 2: Convert to fraction form
    401.90/554.49 = 318.75/x
  3. Step 3: Cross multiply
    401.90x = 554.49 × 318.75
  4. Step 4: Simplify right side
    401.90x = 176,741.61
  5. Step 5: Solve for x
    x = 176,741.61/401.90
  6. Step 6: Final answer
    x = 439.77

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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.