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Finding the Fourth Proportional to 347.82, 521.55 and 128.28

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Solution

The fourth proportional to 347.82, 521.55 and 128.28 is: 192.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    347.82 : 521.55 = 128.28 : x
  2. Step 2: Convert to fraction form
    347.82/521.55 = 128.28/x
  3. Step 3: Cross multiply
    347.82x = 521.55 × 128.28
  4. Step 4: Simplify right side
    347.82x = 66,904.43
  5. Step 5: Solve for x
    x = 66,904.43/347.82
  6. Step 6: Final answer
    x = 192.35

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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.