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Finding the Fourth Proportional to 277.80, 417.60 and 256.20

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Solution

The fourth proportional to 277.80, 417.60 and 256.20 is: 385.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    277.80 : 417.60 = 256.20 : x
  2. Step 2: Convert to fraction form
    277.80/417.60 = 256.20/x
  3. Step 3: Cross multiply
    277.80x = 417.60 × 256.20
  4. Step 4: Simplify right side
    277.80x = 106,989.12
  5. Step 5: Solve for x
    x = 106,989.12/277.80
  6. Step 6: Final answer
    x = 385.13

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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.