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Finding the Fourth Proportional to 782.71, 1,080.16 and 428.64

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Solution

The fourth proportional to 782.71, 1,080.16 and 428.64 is: 591.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.71 : 1,080.16 = 428.64 : x
  2. Step 2: Convert to fraction form
    782.71/1,080.16 = 428.64/x
  3. Step 3: Cross multiply
    782.71x = 1,080.16 × 428.64
  4. Step 4: Simplify right side
    782.71x = 463,000.13
  5. Step 5: Solve for x
    x = 463,000.13/782.71
  6. Step 6: Final answer
    x = 591.53

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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.