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Finding the Fourth Proportional to 745.12, 1,028.40 and 434.80

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Solution

The fourth proportional to 745.12, 1,028.40 and 434.80 is: 600.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    745.12 : 1,028.40 = 434.80 : x
  2. Step 2: Convert to fraction form
    745.12/1,028.40 = 434.80/x
  3. Step 3: Cross multiply
    745.12x = 1,028.40 × 434.80
  4. Step 4: Simplify right side
    745.12x = 447,148.32
  5. Step 5: Solve for x
    x = 447,148.32/745.12
  6. Step 6: Final answer
    x = 600.10

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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.