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Finding the Fourth Proportional to 666.60, 987.08 and 666.60

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Solution

The fourth proportional to 666.60, 987.08 and 666.60 is: 987.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.60 : 987.08 = 666.60 : x
  2. Step 2: Convert to fraction form
    666.60/987.08 = 666.60/x
  3. Step 3: Cross multiply
    666.60x = 987.08 × 666.60
  4. Step 4: Simplify right side
    666.60x = 657,987.53
  5. Step 5: Solve for x
    x = 657,987.53/666.60
  6. Step 6: Final answer
    x = 987.08

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.