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Finding the Fourth Proportional to 688.12, 948.36 and 491.56

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Solution

The fourth proportional to 688.12, 948.36 and 491.56 is: 677.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.12 : 948.36 = 491.56 : x
  2. Step 2: Convert to fraction form
    688.12/948.36 = 491.56/x
  3. Step 3: Cross multiply
    688.12x = 948.36 × 491.56
  4. Step 4: Simplify right side
    688.12x = 466,175.84
  5. Step 5: Solve for x
    x = 466,175.84/688.12
  6. Step 6: Final answer
    x = 677.46

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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.