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Finding the Fourth Proportional to 918.20, 1,377 and 430.76

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Solution

The fourth proportional to 918.20, 1,377 and 430.76 is: 646.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    918.20 : 1,377 = 430.76 : x
  2. Step 2: Convert to fraction form
    918.20/1,377 = 430.76/x
  3. Step 3: Cross multiply
    918.20x = 1,377 × 430.76
  4. Step 4: Simplify right side
    918.20x = 593,156.52
  5. Step 5: Solve for x
    x = 593,156.52/918.20
  6. Step 6: Final answer
    x = 646.00

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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.