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Finding the Fourth Proportional to 491.10, 668.40 and 491.10

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Solution

The fourth proportional to 491.10, 668.40 and 491.10 is: 668.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.10 : 668.40 = 491.10 : x
  2. Step 2: Convert to fraction form
    491.10/668.40 = 491.10/x
  3. Step 3: Cross multiply
    491.10x = 668.40 × 491.10
  4. Step 4: Simplify right side
    491.10x = 328,251.24
  5. Step 5: Solve for x
    x = 328,251.24/491.10
  6. Step 6: Final answer
    x = 668.40

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.