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Finding the Fourth Proportional to 651.40, 898.70 and 389.32

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Solution

The fourth proportional to 651.40, 898.70 and 389.32 is: 537.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.40 : 898.70 = 389.32 : x
  2. Step 2: Convert to fraction form
    651.40/898.70 = 389.32/x
  3. Step 3: Cross multiply
    651.40x = 898.70 × 389.32
  4. Step 4: Simplify right side
    651.40x = 349,881.88
  5. Step 5: Solve for x
    x = 349,881.88/651.40
  6. Step 6: Final answer
    x = 537.12

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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.