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Finding the Fourth Proportional to 387.64, 580.98 and 205

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Solution

The fourth proportional to 387.64, 580.98 and 205 is: 307.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.64 : 580.98 = 205 : x
  2. Step 2: Convert to fraction form
    387.64/580.98 = 205/x
  3. Step 3: Cross multiply
    387.64x = 580.98 × 205
  4. Step 4: Simplify right side
    387.64x = 119,100.90
  5. Step 5: Solve for x
    x = 119,100.90/387.64
  6. Step 6: Final answer
    x = 307.25

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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.