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Finding the Fourth Proportional to 783.58, 1,080.91 and 499.47

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Solution

The fourth proportional to 783.58, 1,080.91 and 499.47 is: 688.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.58 : 1,080.91 = 499.47 : x
  2. Step 2: Convert to fraction form
    783.58/1,080.91 = 499.47/x
  3. Step 3: Cross multiply
    783.58x = 1,080.91 × 499.47
  4. Step 4: Simplify right side
    783.58x = 539,882.12
  5. Step 5: Solve for x
    x = 539,882.12/783.58
  6. Step 6: Final answer
    x = 688.99

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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.