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Finding the Fourth Proportional to 388.08, 581.58 and 266.40

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Solution

The fourth proportional to 388.08, 581.58 and 266.40 is: 399.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.08 : 581.58 = 266.40 : x
  2. Step 2: Convert to fraction form
    388.08/581.58 = 266.40/x
  3. Step 3: Cross multiply
    388.08x = 581.58 × 266.40
  4. Step 4: Simplify right side
    388.08x = 154,932.91
  5. Step 5: Solve for x
    x = 154,932.91/388.08
  6. Step 6: Final answer
    x = 399.23

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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.