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Finding the Fourth Proportional to 385.40, 577.20 and 192.80

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Solution

The fourth proportional to 385.40, 577.20 and 192.80 is: 288.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.40 : 577.20 = 192.80 : x
  2. Step 2: Convert to fraction form
    385.40/577.20 = 192.80/x
  3. Step 3: Cross multiply
    385.40x = 577.20 × 192.80
  4. Step 4: Simplify right side
    385.40x = 111,284.16
  5. Step 5: Solve for x
    x = 111,284.16/385.40
  6. Step 6: Final answer
    x = 288.75

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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.