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Finding the Fourth Proportional to 747.12, 1,120.80 and 490.80

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Solution

The fourth proportional to 747.12, 1,120.80 and 490.80 is: 736.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    747.12 : 1,120.80 = 490.80 : x
  2. Step 2: Convert to fraction form
    747.12/1,120.80 = 490.80/x
  3. Step 3: Cross multiply
    747.12x = 1,120.80 × 490.80
  4. Step 4: Simplify right side
    747.12x = 550,088.64
  5. Step 5: Solve for x
    x = 550,088.64/747.12
  6. Step 6: Final answer
    x = 736.28

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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.