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Finding the Fourth Proportional to 660.21, 987.67 and 557.74

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Solution

The fourth proportional to 660.21, 987.67 and 557.74 is: 834.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.21 : 987.67 = 557.74 : x
  2. Step 2: Convert to fraction form
    660.21/987.67 = 557.74/x
  3. Step 3: Cross multiply
    660.21x = 987.67 × 557.74
  4. Step 4: Simplify right side
    660.21x = 550,863.07
  5. Step 5: Solve for x
    x = 550,863.07/660.21
  6. Step 6: Final answer
    x = 834.38

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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.