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Finding the Fourth Proportional to 715.30, 986.10 and 493.90

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Solution

The fourth proportional to 715.30, 986.10 and 493.90 is: 680.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    715.30 : 986.10 = 493.90 : x
  2. Step 2: Convert to fraction form
    715.30/986.10 = 493.90/x
  3. Step 3: Cross multiply
    715.30x = 986.10 × 493.90
  4. Step 4: Simplify right side
    715.30x = 487,034.79
  5. Step 5: Solve for x
    x = 487,034.79/715.30
  6. Step 6: Final answer
    x = 680.88

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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.