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Finding the Fourth Proportional to 378.16, 521.86 and 228.79

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Solution

The fourth proportional to 378.16, 521.86 and 228.79 is: 315.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.16 : 521.86 = 228.79 : x
  2. Step 2: Convert to fraction form
    378.16/521.86 = 228.79/x
  3. Step 3: Cross multiply
    378.16x = 521.86 × 228.79
  4. Step 4: Simplify right side
    378.16x = 119,393.92
  5. Step 5: Solve for x
    x = 119,393.92/378.16
  6. Step 6: Final answer
    x = 315.73

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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.