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Finding the Fourth Proportional to 378.15, 521.80 and 228.80

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Solution

The fourth proportional to 378.15, 521.80 and 228.80 is: 315.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.15 : 521.80 = 228.80 : x
  2. Step 2: Convert to fraction form
    378.15/521.80 = 228.80/x
  3. Step 3: Cross multiply
    378.15x = 521.80 × 228.80
  4. Step 4: Simplify right side
    378.15x = 119,386.70
  5. Step 5: Solve for x
    x = 119,386.70/378.15
  6. Step 6: Final answer
    x = 315.71

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.