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Finding the Fourth Proportional to 654.90, 981.65 and 380.42

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Solution

The fourth proportional to 654.90, 981.65 and 380.42 is: 570.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.90 : 981.65 = 380.42 : x
  2. Step 2: Convert to fraction form
    654.90/981.65 = 380.42/x
  3. Step 3: Cross multiply
    654.90x = 981.65 × 380.42
  4. Step 4: Simplify right side
    654.90x = 373,432.48
  5. Step 5: Solve for x
    x = 373,432.48/654.90
  6. Step 6: Final answer
    x = 570.21

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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.