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Finding the Fourth Proportional to 684.60, 944.84 and 389.90

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Solution

The fourth proportional to 684.60, 944.84 and 389.90 is: 538.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.60 : 944.84 = 389.90 : x
  2. Step 2: Convert to fraction form
    684.60/944.84 = 389.90/x
  3. Step 3: Cross multiply
    684.60x = 944.84 × 389.90
  4. Step 4: Simplify right side
    684.60x = 368,393.12
  5. Step 5: Solve for x
    x = 368,393.12/684.60
  6. Step 6: Final answer
    x = 538.11

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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.