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Finding the Fourth Proportional to 684.60, 944.80 and 389.89

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Solution

The fourth proportional to 684.60, 944.80 and 389.89 is: 538.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.60 : 944.80 = 389.89 : x
  2. Step 2: Convert to fraction form
    684.60/944.80 = 389.89/x
  3. Step 3: Cross multiply
    684.60x = 944.80 × 389.89
  4. Step 4: Simplify right side
    684.60x = 368,368.28
  5. Step 5: Solve for x
    x = 368,368.28/684.60
  6. Step 6: Final answer
    x = 538.08

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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.