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Finding the Fourth Proportional to 493.43, 740.13 and 128.21

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Solution

The fourth proportional to 493.43, 740.13 and 128.21 is: 192.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    493.43 : 740.13 = 128.21 : x
  2. Step 2: Convert to fraction form
    493.43/740.13 = 128.21/x
  3. Step 3: Cross multiply
    493.43x = 740.13 × 128.21
  4. Step 4: Simplify right side
    493.43x = 94,888.37
  5. Step 5: Solve for x
    x = 94,888.37/493.43
  6. Step 6: Final answer
    x = 192.31

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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.