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Finding the Fourth Proportional to 528.39, 729.18 and 307.40

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Solution

The fourth proportional to 528.39, 729.18 and 307.40 is: 424.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.39 : 729.18 = 307.40 : x
  2. Step 2: Convert to fraction form
    528.39/729.18 = 307.40/x
  3. Step 3: Cross multiply
    528.39x = 729.18 × 307.40
  4. Step 4: Simplify right side
    528.39x = 224,146.29
  5. Step 5: Solve for x
    x = 224,146.29/528.39
  6. Step 6: Final answer
    x = 424.21

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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.