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Finding the Fourth Proportional to 557.80, 838.30 and 487.40

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Solution

The fourth proportional to 557.80, 838.30 and 487.40 is: 732.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    557.80 : 838.30 = 487.40 : x
  2. Step 2: Convert to fraction form
    557.80/838.30 = 487.40/x
  3. Step 3: Cross multiply
    557.80x = 838.30 × 487.40
  4. Step 4: Simplify right side
    557.80x = 408,587.42
  5. Step 5: Solve for x
    x = 408,587.42/557.80
  6. Step 6: Final answer
    x = 732.50

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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.