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Finding the Fourth Proportional to 660.04, 987.64 and 399.08

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Solution

The fourth proportional to 660.04, 987.64 and 399.08 is: 597.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.04 : 987.64 = 399.08 : x
  2. Step 2: Convert to fraction form
    660.04/987.64 = 399.08/x
  3. Step 3: Cross multiply
    660.04x = 987.64 × 399.08
  4. Step 4: Simplify right side
    660.04x = 394,147.37
  5. Step 5: Solve for x
    x = 394,147.37/660.04
  6. Step 6: Final answer
    x = 597.16

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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.