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Finding the Fourth Proportional to 728.64, 1,005.27 and 492.90

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Solution

The fourth proportional to 728.64, 1,005.27 and 492.90 is: 680.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    728.64 : 1,005.27 = 492.90 : x
  2. Step 2: Convert to fraction form
    728.64/1,005.27 = 492.90/x
  3. Step 3: Cross multiply
    728.64x = 1,005.27 × 492.90
  4. Step 4: Simplify right side
    728.64x = 495,497.58
  5. Step 5: Solve for x
    x = 495,497.58/728.64
  6. Step 6: Final answer
    x = 680.03

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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.