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Finding the Fourth Proportional to 686.63, 947.55 and 479.99

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Solution

The fourth proportional to 686.63, 947.55 and 479.99 is: 662.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.63 : 947.55 = 479.99 : x
  2. Step 2: Convert to fraction form
    686.63/947.55 = 479.99/x
  3. Step 3: Cross multiply
    686.63x = 947.55 × 479.99
  4. Step 4: Simplify right side
    686.63x = 454,809.79
  5. Step 5: Solve for x
    x = 454,809.79/686.63
  6. Step 6: Final answer
    x = 662.38

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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.