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Finding the Fourth Proportional to 716.18, 988.20 and 519.78

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Solution

The fourth proportional to 716.18, 988.20 and 519.78 is: 717.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    716.18 : 988.20 = 519.78 : x
  2. Step 2: Convert to fraction form
    716.18/988.20 = 519.78/x
  3. Step 3: Cross multiply
    716.18x = 988.20 × 519.78
  4. Step 4: Simplify right side
    716.18x = 513,646.60
  5. Step 5: Solve for x
    x = 513,646.60/716.18
  6. Step 6: Final answer
    x = 717.20

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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.