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Finding the Fourth Proportional to 686.64, 1,030 and 199.68

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Solution

The fourth proportional to 686.64, 1,030 and 199.68 is: 299.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.64 : 1,030 = 199.68 : x
  2. Step 2: Convert to fraction form
    686.64/1,030 = 199.68/x
  3. Step 3: Cross multiply
    686.64x = 1,030 × 199.68
  4. Step 4: Simplify right side
    686.64x = 205,670.40
  5. Step 5: Solve for x
    x = 205,670.40/686.64
  6. Step 6: Final answer
    x = 299.53

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.