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Finding the Fourth Proportional to 388.19, 581.61 and 278.31

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Solution

The fourth proportional to 388.19, 581.61 and 278.31 is: 416.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.19 : 581.61 = 278.31 : x
  2. Step 2: Convert to fraction form
    388.19/581.61 = 278.31/x
  3. Step 3: Cross multiply
    388.19x = 581.61 × 278.31
  4. Step 4: Simplify right side
    388.19x = 161,867.12
  5. Step 5: Solve for x
    x = 161,867.12/388.19
  6. Step 6: Final answer
    x = 416.98

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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.