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Finding the Fourth Proportional to 630.87, 870.36 and 394.72

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Solution

The fourth proportional to 630.87, 870.36 and 394.72 is: 544.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.87 : 870.36 = 394.72 : x
  2. Step 2: Convert to fraction form
    630.87/870.36 = 394.72/x
  3. Step 3: Cross multiply
    630.87x = 870.36 × 394.72
  4. Step 4: Simplify right side
    630.87x = 343,551.96
  5. Step 5: Solve for x
    x = 343,551.96/630.87
  6. Step 6: Final answer
    x = 544.57

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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.