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Finding the Fourth Proportional to 687.60, 949.86 and 515.07

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Solution

The fourth proportional to 687.60, 949.86 and 515.07 is: 711.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.60 : 949.86 = 515.07 : x
  2. Step 2: Convert to fraction form
    687.60/949.86 = 515.07/x
  3. Step 3: Cross multiply
    687.60x = 949.86 × 515.07
  4. Step 4: Simplify right side
    687.60x = 489,244.39
  5. Step 5: Solve for x
    x = 489,244.39/687.60
  6. Step 6: Final answer
    x = 711.52

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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.