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Finding the Fourth Proportional to 528.12, 728.70 and 307.09

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Solution

The fourth proportional to 528.12, 728.70 and 307.09 is: 423.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.12 : 728.70 = 307.09 : x
  2. Step 2: Convert to fraction form
    528.12/728.70 = 307.09/x
  3. Step 3: Cross multiply
    528.12x = 728.70 × 307.09
  4. Step 4: Simplify right side
    528.12x = 223,776.24
  5. Step 5: Solve for x
    x = 223,776.24/528.12
  6. Step 6: Final answer
    x = 423.72

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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.