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Finding the Fourth Proportional to 654.30, 902.70 and 392.40

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Solution

The fourth proportional to 654.30, 902.70 and 392.40 is: 541.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.30 : 902.70 = 392.40 : x
  2. Step 2: Convert to fraction form
    654.30/902.70 = 392.40/x
  3. Step 3: Cross multiply
    654.30x = 902.70 × 392.40
  4. Step 4: Simplify right side
    654.30x = 354,219.48
  5. Step 5: Solve for x
    x = 354,219.48/654.30
  6. Step 6: Final answer
    x = 541.37

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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.