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Finding the Fourth Proportional to 686.81, 1,030.34 and 357.90

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Solution

The fourth proportional to 686.81, 1,030.34 and 357.90 is: 536.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.81 : 1,030.34 = 357.90 : x
  2. Step 2: Convert to fraction form
    686.81/1,030.34 = 357.90/x
  3. Step 3: Cross multiply
    686.81x = 1,030.34 × 357.90
  4. Step 4: Simplify right side
    686.81x = 368,756.90
  5. Step 5: Solve for x
    x = 368,756.90/686.81
  6. Step 6: Final answer
    x = 536.92

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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.