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Finding the Fourth Proportional to 870.81, 1,306.64 and 408.52

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Solution

The fourth proportional to 870.81, 1,306.64 and 408.52 is: 612.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.81 : 1,306.64 = 408.52 : x
  2. Step 2: Convert to fraction form
    870.81/1,306.64 = 408.52/x
  3. Step 3: Cross multiply
    870.81x = 1,306.64 × 408.52
  4. Step 4: Simplify right side
    870.81x = 533,788.57
  5. Step 5: Solve for x
    x = 533,788.57/870.81
  6. Step 6: Final answer
    x = 612.98

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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.