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Finding the Fourth Proportional to 654.64, 981.65 and 380.81

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Solution

The fourth proportional to 654.64, 981.65 and 380.81 is: 571.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.64 : 981.65 = 380.81 : x
  2. Step 2: Convert to fraction form
    654.64/981.65 = 380.81/x
  3. Step 3: Cross multiply
    654.64x = 981.65 × 380.81
  4. Step 4: Simplify right side
    654.64x = 373,822.69
  5. Step 5: Solve for x
    x = 373,822.69/654.64
  6. Step 6: Final answer
    x = 571.04

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.