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Finding the Fourth Proportional to 651.21, 898.31 and 389.07

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Solution

The fourth proportional to 651.21, 898.31 and 389.07 is: 536.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.21 : 898.31 = 389.07 : x
  2. Step 2: Convert to fraction form
    651.21/898.31 = 389.07/x
  3. Step 3: Cross multiply
    651.21x = 898.31 × 389.07
  4. Step 4: Simplify right side
    651.21x = 349,503.53
  5. Step 5: Solve for x
    x = 349,503.53/651.21
  6. Step 6: Final answer
    x = 536.70

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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.