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Finding the Fourth Proportional to 666.91, 920.57 and 401.50

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Solution

The fourth proportional to 666.91, 920.57 and 401.50 is: 554.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.91 : 920.57 = 401.50 : x
  2. Step 2: Convert to fraction form
    666.91/920.57 = 401.50/x
  3. Step 3: Cross multiply
    666.91x = 920.57 × 401.50
  4. Step 4: Simplify right side
    666.91x = 369,610.65
  5. Step 5: Solve for x
    x = 369,610.65/666.91
  6. Step 6: Final answer
    x = 554.21

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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.