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Finding the Fourth Proportional to 493.80, 740.74 and 128.63

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Solution

The fourth proportional to 493.80, 740.74 and 128.63 is: 192.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    493.80 : 740.74 = 128.63 : x
  2. Step 2: Convert to fraction form
    493.80/740.74 = 128.63/x
  3. Step 3: Cross multiply
    493.80x = 740.74 × 128.63
  4. Step 4: Simplify right side
    493.80x = 95,277.36
  5. Step 5: Solve for x
    x = 95,277.36/493.80
  6. Step 6: Final answer
    x = 192.95

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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.