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Finding the Fourth Proportional to 630.38, 870.32 and 406.70

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Solution

The fourth proportional to 630.38, 870.32 and 406.70 is: 561.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.38 : 870.32 = 406.70 : x
  2. Step 2: Convert to fraction form
    630.38/870.32 = 406.70/x
  3. Step 3: Cross multiply
    630.38x = 870.32 × 406.70
  4. Step 4: Simplify right side
    630.38x = 353,959.14
  5. Step 5: Solve for x
    x = 353,959.14/630.38
  6. Step 6: Final answer
    x = 561.50

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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.