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Finding the Fourth Proportional to 742.88, 1,025.32 and 428.20

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Solution

The fourth proportional to 742.88, 1,025.32 and 428.20 is: 591.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    742.88 : 1,025.32 = 428.20 : x
  2. Step 2: Convert to fraction form
    742.88/1,025.32 = 428.20/x
  3. Step 3: Cross multiply
    742.88x = 1,025.32 × 428.20
  4. Step 4: Simplify right side
    742.88x = 439,042.02
  5. Step 5: Solve for x
    x = 439,042.02/742.88
  6. Step 6: Final answer
    x = 591.00

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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.